Backport "Remove double tests of tests/pos" to LTS (#20702)

Backports #18683 to the LTS branch.

PR submitted by the release tooling.
[skip ci]

Author: WojciechMazur

compiler/test/dotty/tools/dotc/CompilationTests.scala

@@ -33,7 +33,6 @@ class CompilationTests {
       compileFilesInDir("tests/pos", defaultOptions.and("-Ysafe-init")),
       compileFilesInDir("tests/pos-deep-subtype", allowDeepSubtypes),
       compileFilesInDir("tests/pos-special/sourcepath/outer", defaultOptions.and("-sourcepath", "tests/pos-special/sourcepath")),
-      compileFilesInDir("tests/pos", defaultOptions.and("-Xlint:private-shadow", "-Xlint:type-parameter-shadow")),
       compileFile("tests/pos-special/sourcepath/outer/nested/Test4.scala", defaultOptions.and("-sourcepath", "tests/pos-special/sourcepath")),
       compileFilesInDir("tests/pos-scala2", defaultOptions.and("-source", "3.0-migration")),
       compileFilesInDir("tests/pos-custom-args/captures", defaultOptions.and("-language:experimental.captureChecking")),