Add outstanding token airdrops to REST API

[edwin-greene]

Description: Adds the outstanding token airdrops endpoint to the REST API.

Related issue(s):

Fixes #8276

Notes for reviewer: Currently only supports fungible token airdrops.

Checklist

• [x] Documented (Code comments, README, etc.)
• [x] Tested (unit, integration, etc.)

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 93.49593% with 8 lines in your changes missing coverage. Please review.

Project coverage is 92.55%. Comparing base (307c002) to head (8c0abbc). Report is 22 commits behind head on main.

Files with missing lines	Patch %	Lines
...era/mirror/restjava/repository/JooqRepository.java	91.66%	1 Missing and 3 partials :warning:
...edera/mirror/restjava/mapper/CollectionMapper.java	71.42%	1 Missing and 1 partial :warning:
...a/repository/TokenAirdropRepositoryCustomImpl.java	90.90%	0 Missing and 2 partials :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #9286 +/- ## ============================================ - Coverage 93.15% 92.55% -0.61% - Complexity 1092 7039 +5947 ============================================ Files 363 912 +549 Lines 11285 29760 +18475 Branches 1642 3760 +2118 ============================================ + Hits 10513 27543 +17030 - Misses 633 1446 +813 - Partials 139 771 +632 ```

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[xin-hedera]

Pagination by serialnumber may be added later.

Can this even work?

Serial number should be in the order part so as to limit the entries in the response. If we don't support seiral number pagination, we won't have it in the next url, then wouldn't the endpoint provide incomplete response? Or duplicate info? Or even stuck and never get to the next page?

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud