[stable-2.19] Update License Header and Add New Operation

[backportbot]

Backport of PR #1523

[github-actions]

SpotBugs

Category	Base	New
Bad practice	35	35
Correctness	34	34
Dodgy code	26	26
Internationalization	6	6
Malicious code vulnerability	49	49
Multithreaded correctness	3	3
Performance	8	8
Total	161	161

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 24 lines in your changes missing coverage. Please review.

Project coverage is 48.80%. Comparing base (b884b0a) to head (2215a02).

Files with missing lines	Patch %	Lines
...sources/users/GetServerPublicKeyRemoteOperation.kt	0.00%	24 Missing ⚠️

Additional details and impacted files

@@                Coverage Diff                @@
##             stable-2.19    #1637      +/-   ##
=================================================
+ Coverage          47.60%   48.80%   +1.20%     
- Complexity           990      997       +7     
=================================================
  Files                207      207              
  Lines               7923     7857      -66     
  Branches            1023     1021       -2     
=================================================
+ Hits                3772     3835      +63     
+ Misses              3611     3473     -138     
- Partials             540      549       +9     

Files with missing lines	Coverage Δ
...owncloud/android/lib/common/network/WebdavEntry.kt	82.82% <ø> (+2.14%)	⬆️
...ncloud/android/lib/common/network/WebdavUtils.java	88.80% <ø> (ø)
...sources/users/GetServerPublicKeyRemoteOperation.kt	0.00% <0.00%> (ø)

... and 36 files with indirect coverage changes

[alperozturk96]

This PR is needed

[github-actions]

SpotBugs

Category	Base	New
Bad practice	35	35
Correctness	34	34
Dodgy code	26	26
Internationalization	6	6
Malicious code vulnerability	49	49
Multithreaded correctness	3	3
Performance	8	8
Total	161	161

[github-actions]

SpotBugs

Category	Base	New
Bad practice	35	35
Correctness	34	34
Dodgy code	26	26
Internationalization	6	6
Malicious code vulnerability	49	49
Multithreaded correctness	3	3
Performance	8	8
Total	161	161

[nextcloud-android-bot]

master-IT test failed: https://www.kaminsky.me/nc-dev/library-integrationTests/3821-IT-master-11-12/debug/