Bump dependencies, code quality, fix minor bugs

[fwdekker]

A slew of minor and mostly inconsequential updates for the beta version. Ensures the beta version is ready for the coming months :-)

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• Updates dependencies, plugins, and Gradle
• Fixes style issues detected by latest version of Detekt
• Replaces usage of the Spek library with Kotest
• Removes incompatible IDEA API usages

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• Improves documentation of warning suppressions
• Documents how to choose compatibility with Java and Kotlin versions in gradle.properties
• Updates acknowledgements in README.md
• Updates the .gitignore
• Finally completely removes verifier.gradle

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• Fixes (231+) Move to Java 17 #448
• Fixes "No displayName is specified for configurable: com.fwdekker.randomness.integer.IntegerSettingsConfigurable" #459 for the beta version as well
• Fixes a bug where modifiers were not detected during insertion
• Fixes a bug where the order of radio buttons in the array settings was incorrect

[codecov]

Codecov Report

Merging #462 (42ea805) into main (02d6326) will increase coverage by 1.51%.
The diff coverage is 72.88%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #462      +/-   ##
==========================================
+ Coverage   83.01%   84.53%   +1.51%     
==========================================
  Files          52       52              
  Lines        1849     1862      +13     
  Branches      348      342       -6     
==========================================
+ Hits         1535     1574      +39     
+ Misses        258      247      -11     
+ Partials       56       41      -15