build: do not change license header to SPDX format

[jjohannes]

Description:

Reverts moving to a new license header already, which was part of #15282

Related issue(s):
#15282
hiero-ledger/hiero-gradle-conventions#48

Notes for reviewer:

Checklist

• Tested (unit, integration, etc.)

[codacy-production]

Coverage summary from Codacy

See diff coverage on Codacy

Coverage variation	Diff coverage
✅ +0.00% (target: -1.00%)	✅ ∅

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (1128c74)	95476	64916	67.99%
Head commit (98dd6f8)	95476 (+0)	64912 (-4)	67.99% (+0.00%)

Coverage variation is the difference between the coverage for the head and common ancestor commits of the pull request branch: <coverage of head commit> - <coverage of common ancestor commit>

Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#17132)	0	0	∅ (not applicable)

Diff coverage is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: <covered lines added or modified>/<coverable lines added or modified> * 100%

See your quality gate settings    Change summary preferences

_{Codacy stopped sending the deprecated coverage status on June 5th, 2024. Learn more}

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 64.24%. Comparing base (1128c74) to head (98dd6f8).
Report is 1 commits behind head on develop.

Additional details and impacted files

@@              Coverage Diff              @@
##             develop   #17132      +/-   ##
=============================================
- Coverage      64.25%   64.24%   -0.01%     
+ Complexity     20819    20818       -1     
=============================================
  Files           2547     2547              
  Lines          95713    95713              
  Branches       10014    10014              
=============================================
- Hits           61498    61494       -4     
- Misses         30606    30610       +4     
  Partials        3609     3609              

see 6 files with indirect coverage changes

[mishomihov00]

LGTM