Compile with Java 21

[mateuszkwiecinski]

blocked by https://issuetracker.google.com/issues/294137077

[github-actions]

Diffuse output:

OLD: diffuse-base-file
NEW: android.jar

       │          compressed          │          uncompressed          
       ├──────────┬──────────┬────────┼───────────┬───────────┬────────
 JAR   │ old      │ new      │ diff   │ old       │ new       │ diff   
───────┼──────────┼──────────┼────────┼───────────┼───────────┼────────
 class │ 58.3 KiB │ 58.1 KiB │ -222 B │ 124.9 KiB │ 124.3 KiB │ -643 B 
 other │  2.3 KiB │  2.3 KiB │    0 B │     345 B │     345 B │    0 B 
───────┼──────────┼──────────┼────────┼───────────┼───────────┼────────
 total │ 60.6 KiB │ 60.4 KiB │ -222 B │ 125.2 KiB │ 124.6 KiB │ -643 B 

 CLASSES │ old │ new │ diff       
─────────┼─────┼─────┼────────────
 classes │  34 │  34 │  0 (+0 -0) 
 methods │ 249 │ 247 │ -2 (+0 -2) 
  fields │  40 │  40 │  0 (+0 -0)

JAR

    compressed    │   uncompressed    │                                                                            
─────────┬────────┼──────────┬────────┤                                                                            
 size    │ diff   │ size     │ diff   │ path                                                                       
─────────┼────────┼──────────┼────────┼────────────────────────────────────────────────────────────────────────────
   3 KiB │ -221 B │  8.6 KiB │ -643 B │ ∆ com/project/starter/modules/plugins/AndroidLibraryPlugin.class           
 1.3 KiB │   -1 B │    2 KiB │    0 B │ ∆ com/project/starter/modules/plugins/AndroidLibraryPlugin_apply_1_2.class 
─────────┼────────┼──────────┼────────┼────────────────────────────────────────────────────────────────────────────
 4.3 KiB │ -222 B │ 10.6 KiB │ -643 B │ (total)

CLASSES

METHODS:

   old │ new │ diff       
  ─────┼─────┼────────────
   249 │ 247 │ -2 (+0 -2) 
  - com.android.build.api.dsl.LibraryDefaultConfig setTargetSdk(Integer)
  - com.android.build.api.dsl.LibraryExtension getDefaultConfig() → DefaultConfig

[codecov]

Codecov Report

Merging #547 (67ce0b4) into master (09718c4) will increase coverage by 0.15%.
The diff coverage is 100.00%.

@@             Coverage Diff              @@
##             master     #547      +/-   ##
============================================
+ Coverage     82.07%   82.22%   +0.15%     
  Complexity       46       46              
============================================
  Files            28       28              
  Lines           541      540       -1     
  Branches         43       42       -1     
============================================
  Hits            444      444              
  Misses           74       74              
+ Partials         23       22       -1     

Files	Coverage Δ
...ct/starter/modules/plugins/AndroidLibraryPlugin.kt	100.00% <ø> (+5.00%)	⬆️
...m/project/starter/quality/plugins/QualityPlugin.kt	50.00% <100.00%> (ø)