Remove attachments enabling flag

[SupunS]

Description

Attachments are enabled on all networks now. So the flag is no longer needed.

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• Targeted PR against master branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[github-actions]

Cadence Benchstat comparison

This branch with compared with the base branch onflow:master commit 85f46f7
The command for i in {1..N}; do go test ./... -run=XXX -bench=. -benchmem -shuffle=on; done was used.
Bench tests were run a total of 7 times on each branch.

Collapsed results for better readability

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.20%. Comparing base (d90d449) to head (0e1b932).
Report is 68 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3642      +/-   ##
==========================================
- Coverage   80.53%   80.20%   -0.33%     
==========================================
  Files         432      411      -21     
  Lines       97964    95543    -2421     
==========================================
- Hits        78891    76629    -2262     
+ Misses      16321    16228      -93     
+ Partials     2752     2686      -66     

Flag	Coverage Δ
unittests	80.20% <ø> (-0.33%)	⬇️

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[SupunS]

The backward compatibility checker fails due to missing 5f195aa4322e5dbb.EVMHelper:71(5:2):*sema.AttachmentsNotEnabledError error, because the analyzer tool didn't have the attachments enabled flag on. So this is expected.

Interestingly, seems EVMHelper is the only one using attachments at the moment 😄

[turbolent]

Nice!