[Fix] jsx-newline: No newline between comments and jsx elements

[justmejulian]

Fixes #3478 and #2926 and adds a couple more tests to show what was failing.

From what I can gather this should be the default behaviour. If not then then this can be hidden behind an option.

I was not sure about the behaviour of multiple Block comments before a Multiline Component. Decided the comments should stick together, based on sujan-s comment in #3478.

[codecov]

Codecov Report

Merging #3493 (34a9d4f) into master (54c56a1) will decrease coverage by 0.12%.
The diff coverage is 100.00%.

❗ Current head 34a9d4f differs from pull request most recent head 12e9838. Consider uploading reports for the commit 12e9838 to get more accurate results

@@            Coverage Diff             @@
##           master    #3493      +/-   ##
==========================================
- Coverage   97.57%   97.44%   -0.13%     
==========================================
  Files         129      129              
  Lines        9200     9210      +10     
  Branches     3336     3341       +5     
==========================================
- Hits         8977     8975       -2     
- Misses        223      235      +12     

Impacted Files	Coverage Δ
lib/rules/jsx-newline.js	100.00% <100.00%> (ø)
lib/rules/no-arrow-function-lifecycle.js	89.06% <0.00%> (-9.38%)	⬇️
lib/rules/jsx-curly-spacing.js	91.17% <0.00%> (-2.95%)	⬇️
lib/rules/jsx-props-no-spreading.js	95.65% <0.00%> (-2.18%)	⬇️
lib/util/componentUtil.js	97.33% <0.00%> (-1.34%)	⬇️

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[ljharb]

Test cases look great!