[GOBBLIN-763] Support fields removal for compaction dedup key schema

[zxcware]

Dear Gobblin maintainers,

Please accept this PR. I understand that it will not be reviewed until I have checked off all the steps below!

JIRA

• My PR addresses the following Gobblin JIRA issues and references them in the PR title.
  • https://issues.apache.org/jira/browse/GOBBLIN-763

Description

• Here are some details about my PR:
• Remove fields, specified by configuration compaction.job.key.fieldBlacklist, while computing compaction dedup key schema
• Fix incorrect AvroUtils.removeUncomparableFields implementation, which only keeps the first field of any schema, dropping all other fields which have the same schema.

Tests

• My PR adds the following unit tests:
• CompactionJobConfiguratorTest.testKeyFieldBlacklist

Commits

• My commits all reference JIRA issues in their subject lines, and I have squashed multiple commits if they address the same issue. In addition, my commits follow the guidelines from "How to write a good git commit message":
  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters
  3. Subject does not end with a period
  4. Subject uses the imperative mood ("add", not "adding")
  5. Body wraps at 72 characters
  6. Body explains "what" and "why", not "how"

[zxcware]

@yukuai518 @autumnust Please review.

[yukuai518]

+1 LGTM

[htran1]

+1