test(ingest): use different mysql test port

[hsheth2]

Somehow the 53306 port is often in use on the CI machines and causes
conflicts. This changes to a slightly different port number.

For example, from https://github.com/linkedin/datahub/runs/2604009138:

E           ERROR: for testmysql  Cannot start service testmysql: driver failed programming external connectivity on endpoint testmysql (c764a27faba8d8643e59c223bfe06200665704ac4572e254140387e6aa382080): Error starting userland proxy: listen tcp4 0.0.0.0:53306: bind: address already in use
E           Encountered errors while bringing up the project.
E           """.

Checklist

• The PR conforms to DataHub's Contributing Guideline (particularly Commit Message Format)
• Links to related issues (if applicable)
• Tests for the changes have been added/updated (if applicable)
• Docs related to the changes have been added/updated (if applicable)

[shirshanka]

LGTM!
But I'm a bit surprised we are hitting bind port issues.
Quite likely we will run into this even after this change because we might be tripping on ourselves here.