fix(imagemap_alt_exists) remap fail and pass code

[philljenkins]

#1386

remapping the fail and pass code will allow reporting to be correct, including the list of rules and reasons mapped to Requirements as displayed in https://unpkg.com/accessibility-checker-engine@next/help/rules.html

Rule/Engine updates:

• fixrule(imagemap_alt_exists): remap fail and pass code

• Rule bug: imagemap_alt_exists

This PR is related to the following issue(s):

#1386

Additional information can be found here:

Testing reference:

I have conducted the following for this PR:

• I validated this code in Chrome and FF
• I validated this fix in my local env
• I provided details for testing
• This PR has been reviewed and is ready for test
• I understand that the title of this PR will be used for the next release notes.