RFR: 6929: Remove obsolete .hgignore file

[Christoph Dreis]

Hi,

this PR removes the `.hgignore` file that seems obsolete after the move to Git(Hub).

Since this is my first PR to the project, I hope this is loosely following other JDK projects.

This would need a ticket in the bug tracker and I hope you can create this for me. I've signed the OCA for the OpenJDK
already, but let me know if I need to confirm something again.

In case you think this is worthwhile, I would appreciate it if this is sponsored.

Cheers,
Christoph

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Commit messages:
 - Remove obsolete .hgignore

Changes: https://git.openjdk.java.net/jmc/pull/125/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jmc&pr=125&range=00
  Issue: https://bugs.openjdk.java.net/browse/JMC-6929
  Stats: 31 lines in 1 file changed: 0 ins; 31 del; 0 mod
  Patch: https://git.openjdk.java.net/jmc/pull/125.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc pull/125/head:pull/125

PR: https://git.openjdk.java.net/jmc/pull/125