Revert "Make lots of tests run in parallel"

This reverts commit 323dc60712.

Reason for revert: Possible cause of test instability
Bug: 170513220
Test: soong tests

Change-Id: Iee168e9fbb4210569e6cffcc23e60d111403abb8

jar/jar_test.go

@@ -21,7 +21,6 @@ import (
 )
 
 func TestGetJavaPackage(t *testing.T) {
-	t.Parallel()
 	type args struct {
 		r   io.Reader
 		src string
@@ -79,7 +78,6 @@ func TestGetJavaPackage(t *testing.T) {
 }
 
 func Test_javaIdentRune(t *testing.T) {
-	t.Parallel()
 	// runes that should be valid anywhere in an identifier
 	validAnywhere := []rune{
 		// letters, $, _