Move all pickling tests to pos

Author: OlivierBlanvillain

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

@@ -183,7 +183,6 @@ class CompilationTests extends ParallelTesting {
   @Test def pickling: Unit = {
     implicit val testGroup: TestGroup = TestGroup("testPickling")
     compileFilesInDir("tests/new", picklingOptions) +
-    compileFilesInDir("tests/pickling", picklingOptions) +
     compileFilesInDir("tests/pos", picklingOptions, FileFilter.exclude(TestSources.posTestPicklingBlacklisted)) +
     compileFilesInDir("tests/run", picklingOptions, FileFilter.exclude(TestSources.runTestPicklingBlacklisted))
   }.checkCompile()