unify test-kotlin1 and test-kotlin2 into test-kotlin

Delete test-kotlin1 (K1 expected output) and test-kotlin2 (K2 expected
output) and replace them with the unified test-kotlin pack
(codeql/java-kotlin-tests). The expected files come from test-kotlin2 as
updated by the preceding extractor commit, which already aligned K1 and
K2 output for the properties and accessor location improvements.

The unified pack runs against both language modes:
  * -language-version 1.9 (K1 compatibility mode, e.g. for CI)
  * -language-version 2.0 / default K2 (standard mode)

A follow-up CI commit will wire both modes into the workflow generator.

Update CODEOWNERS and labeler.yml to reference test-kotlin instead of
test-kotlin1 / test-kotlin2.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: andersfugmann

.github/labeler.yml

@@ -20,7 +20,7 @@ JS:
 
 Kotlin:
   - java/kotlin-extractor/**/*
-  - java/ql/test-kotlin*/**/*
+  - java/ql/test-kotlin/**/*
 
 Python:
   - python/**/*

CODEOWNERS

@@ -28,8 +28,7 @@
 /swift/extractor/ @github/codeql-swift @github/code-scanning-language-coverage
 /misc/codegen/ @github/codeql-swift
 /java/kotlin-extractor/ @github/codeql-kotlin @github/code-scanning-language-coverage
-/java/ql/test-kotlin1/ @github/codeql-kotlin
-/java/ql/test-kotlin2/ @github/codeql-kotlin
+/java/ql/test-kotlin/ @github/codeql-kotlin
 
 # Experimental CodeQL cryptography
 **/experimental/**/quantum/ @github/ps-codeql