Update tlJdkRelease doc

Author: armanbilge

docs/customization.md

@@ -35,7 +35,7 @@ Instead of using the super-plugins, for finer-grained control you can always add
 ### sbt-typelevel-settings
 - `TypelevelSettingsPlugin`: Good and/or opinionated defaults for scalac settings etc., inspired by sbt-tpolecat.
 - `tlFatalWarnings` (setting): Convert compiler warnings into errors (default: false).
-- `tlJdkRelease` (setting): JVM target version for the compiled bytecode (default: None).
+- `tlJdkRelease` (setting): JVM target version for the compiled bytecode (default: Some(8)).
 
 ### sbt-typelevel-github
 - `TypelevelGitHubPlugin`: Populates boilerplate settings assuming you are using GitHub.

settings/src/main/scala/org/typelevel/sbt/TypelevelSettingsPlugin.scala

@@ -37,7 +37,7 @@ object TypelevelSettingsPlugin extends AutoPlugin {
       settingKey[Boolean]("Convert compiler warnings into errors (default: false)")
     lazy val tlJdkRelease =
       settingKey[Option[Int]](
-        "JVM target version for the compiled bytecode, None results in default scalac and javac behavior (no --release flag is specified). (default: None, supported values: 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)")
+        "JVM target version for the compiled bytecode, None results in default scalac and javac behavior (no compiler flag is added) (default: Some(8))")
   }
 
   import autoImport._