Fix W3C validator issues

[sergejmueller]

Description

Following issues are reported by the W3C validator and have been fixed.

1. Remove unused double quotes
2. Remove duplicate meta description
3. Remove unnecessary type for JS
4. Remove useless async attribute from script
5. Move footer includes into body tag
6. Add missign alt attributes

Testing

✓ Frontend tests

[codecov]

Codecov Report

Merging #5201 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #5201   +/-   ##
=======================================
  Coverage   30.81%   30.81%           
=======================================
  Files         221      221           
  Lines       17804    17804           
  Branches     2457     2457           
=======================================
  Hits         5487     5487           
  Misses      12091    12091           
  Partials      226      226

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[danlipert]

Nice! Thanks for these fixes! Just a few questions I had but looks good to me!

[octavioamu]

good maybe a good idea to move the other scripts behind this comment also inside of body

[sergejmueller]

Actually yes, but I have based myself on existing webpages:

web/app/dashboard/templates/bounty/increase.html

Lines 162 to 192 in 6505bd5

	{% include 'shared/bottom_notification.html' %}
	{% include 'shared/analytics.html' %}
	{% include 'shared/footer_scripts.html' %}
	{% include 'shared/footer.html' %}
	{% include 'shared/messages.html' %}
	</body>
	<script>
	document.is_funder_github_user_same = {{ is_funder }};
	document.FEE_PERCENTAGE = {{ FEE_PERCENTAGE }};
	</script>
	<script src="{% static "v2/js/pages/wallet_estimate.js" %}"></script>
	<script src="{% static "v2/js/lib/ipfs-api.js" %}"></script>
	<script src="{% static "v2/js/ipfs.js" %}"></script>
	<script src="{% static "v2/js/lib/secrets.min.js" %}"></script>
	<script src="{% static "v2/js/ethereumjs-accounts.js" %}"></script>
	<script src="{% static "v2/js/lib/ipfs-api.js" %}"></script>
	<script src="{% static "v2/js/ipfs.js" %}"></script>
	<script src="{% static "v2/js/amounts.js" %}"></script>
	<script src="{% static "v2/js/abi.js" %}"></script>
	<script src="/dynamic/js/tokens_dynamic.js"></script>
	<script src="{% static "v2/js/tokens.js" %}"></script>
	<script src="{% static "v2/js/pages/shared_bounty_mutation_estimate_gas.js" %}"></script>
	<script src="{% static "v2/js/pages/increase_bounty.js" %}"></script>
	<script src="{% static "onepager/js/send.js" %}"></script>
	</html>

web/app/grants/templates/grants/cancel.html

Lines 107 to 125 in 6505bd5

	{% include 'shared/bottom_notification.html' %}
	{% include 'shared/analytics.html' %}
	{% include 'shared/footer_scripts.html' %}
	{% include 'shared/footer.html' %}
	{% include 'grants/shared/shared_scripts.html' %}
	</body>
	<script src="{% static "v2/js/pages/wallet_estimate.js" %}"></script>
	<script src="{% static "v2/js/grants/compiledSplitter.js" %}"></script>
	<script src="{% static "v2/js/grants/compiledSubscriptionContract0.js" %}"></script>
	<script src="{% static "v2/js/grants/compiledSubscriptionContract1.js" %}"></script>
	<script src="{% static "v2/js/grants/compiledTokenContract.js" %}"></script>
	<script src="{% static "v2/js/abi.js" %}"></script>
	<script src="{% static "v2/js/pages/shared_bounty_mutation_estimate_gas.js" %}"></script>
	<script src="{% static "v2/js/lib/ipfs-api.js" %}"></script>
	<script src="{% static "v2/js/ipfs.js" %}"></script>
	<script src="{% static "v2/js/grants/shared.js" %}"></script>
	<script src="{% static "v2/js/waiting_room_entertainment.js" %}"></script>
	<script src="{% static "v2/js/grants/cancel_subscription.js" %}"></script>
	</html>

web/app/grants/templates/grants/fund.html

Lines 355 to 385 in 6505bd5

	{% include 'shared/bottom_notification.html' %}
	{% include 'shared/analytics.html' %}
	{% include 'shared/footer_scripts.html' %}
	{% include 'shared/footer.html' %}
	{% include 'grants/shared/shared_scripts.html' %}
	{% if show_tweet_modal %}
	<script>
	$(document).ready(function(){
	$('#tweetModal').css('display', 'block');
	});
	</script>
	{% endif %}
	</body>
	<script src="{% static "v2/js/pages/wallet_estimate.js" %}"></script>
	<script src="{% static "v2/js/grants/compiledSplitter.js" %}"></script>
	<script src="{% static "v2/js/grants/compiledSubscriptionContract0.js" %}"></script>
	<script src="{% static "v2/js/grants/compiledSubscriptionContract1.js" %}"></script>
	<script src="{% static "v2/js/grants/compiledTokenContract.js" %}"></script>
	<script src="/dynamic/js/tokens_dynamic.js"></script>
	<script src="{% static "v2/js/tokens.js" %}"></script>
	<script src="{% static "v2/js/abi.js" %}"></script>
	<script src="{% static "v2/js/pages/shared_bounty_mutation_estimate_gas.js" %}"></script>
	<script src="{% static "v2/js/grants/shared.js" %}"></script>
	<script src="{% static "v2/js/grants/fund.js" %}"></script>
	<script src="{% static "v2/js/lib/ipfs-api.js" %}"></script>
	<script src="{% static "v2/js/ipfs.js" %}"></script>
	<script src="{% static "v2/js/waiting_room_entertainment.js" %}"></script>
	</html>

[octavioamu]

got it, yes good point we should fix that in some point (not for this PR)