rewriter,restorer: add the DO NOT EDIT comment to the generated Go code

[kennytm]

What problem does this PR solve?

Fix #37.

What is changed and how it works?

This is a resubmission of #39 which puts the comment at the end of the file.

Check List

Tests

• Unit test

Side effects

Related changes

[codecov]

Codecov Report

Merging #42 into master will increase coverage by 0.3519%.
The diff coverage is 63.6363%.

@@               Coverage Diff                @@
##             master        #42        +/-   ##
================================================
+ Coverage   85.9183%   86.2702%   +0.3519%     
================================================
  Files             7          7                
  Lines           980        925        -55     
================================================
- Hits            842        798        -44     
+ Misses           85         80         -5     
+ Partials         53         47         -6     

[kennytm]

This PR is currently blocked by microsoft/vscode-go#2617. The VSCode Go extension only recognize the comment on the first line, so putting the comment at the end won't give us the read-only protection we want.

[CLAassistant]

All committers have signed the CLA.

[tisonkun]

@kennytm is this PR still valid and we can proceed it?

[tisonkun]

Closed as #37 has been marked as resolved.