Added whitespace tolerance for value for ES servers and kafka brokers

[verma-varsha]

Which problem is this PR solving?

• Addresses the issue Strip whitespace from value for ES servers and kafka brokers #1302

Short description of the changes

• A stripWhiteSpace function is added for both ES and kafka
• An additional whitespace is added to the strings used for testing

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@1525c84). Click here to learn what that means.
The diff coverage is 100%.

@@           Coverage Diff            @@
##             master   #1305   +/-   ##
========================================
  Coverage          ?    100%           
========================================
  Files             ?     162           
  Lines             ?    7265           
  Branches          ?       0           
========================================
  Hits              ?    7265           
  Misses            ?       0           
  Partials          ?       0

Impacted Files	Coverage Δ
plugin/storage/kafka/options.go	100% <100%> (ø)
plugin/storage/es/options.go	100% <100%> (ø)

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[karlpokus]

@verma-varsha haha. You beat me to to it :) I also made a PR #1306