Add warning for users visiting Grants page

[sebastiantf]

Description

Adds a warning for users about using Brave Wallet and MetaMask while visiting https://gitcoin.co/grants

Refers/Fixes

Fixes: #5865

Testing

No issues on eslint and stylelint.

[codecov]

Codecov Report

Merging #5988 into master will increase coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #5988      +/-   ##
==========================================
+ Coverage   28.86%   28.89%   +0.02%     
==========================================
  Files         270      270              
  Lines       23742    23742              
  Branches     3454     3454              
==========================================
+ Hits         6854     6860       +6     
+ Misses      16615    16609       -6     
  Partials      273      273

Impacted Files	Coverage Δ
app/dashboard/embed.py	31.6% <0%> (+3.44%)	⬆️

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[thelostone-mc]

@sebastiantf

This would probably be most effective on the /fund page when users are about to contribute to grant and the grant creation page (/grants/new)

What do you think on restricting the alert to just those pages?
Also If we can figure out if user is using brave and only show it then -> it's super effective

a quick google led me to this
https://stackoverflow.com/questions/36523448/how-do-i-tell-if-a-user-is-using-brave-as-their-browser

[sebastiantf]

@thelostone-mc Showing the warning on /fund and /grants/new seems like a good idea. That can be done.

But as I mentioned on the issue page, Brave browser doesn't seem to provide a Brave-specific User Agent which makes detecting Brave browser difficult. See #1052

And since Brave Wallet is a fork of MetaMask, the web3.currentProvider.isMetamask returns true.

So it seems displaying the warning only for Brave users by detecting Brave Browser or Brave Wallet is hard.

The answer in the stackoverflow question also says:

The "Brave" in the user agent was removed in the 0.9 version.

From the changelog:

Removed Brave from the User Agent HTTP header to reduce fingerprinting.

[thelostone-mc]

@sebastiantf let's do it that way !
If I see a way to detect it -> i'll throw that in later

Danke :D

[sebastiantf]

@thelostone-mc Shall I change the warning from /grants to /fund and /grants/new?

[sebastiantf]

@thelostone-mc Please check my new commits and review this PR. I have changed the warning from /grants to /fund and /grants/new

[thelostone-mc]

@sebastiantf Looks good ^_^