Don't link java tests against junit by default

There is more variety of java tests than I expected, don't
default to including junit, that's just going to lead to
unexpected junit classes for module authors that don't know
to set junit: false.  All existing uses of java_test are
already not using junit or setting static_libs: ["junit"],
and all test in Make are already specifying junit.

Bug: 70770641
Test: m checkbuild
Change-Id: I4393b70d87dd2b6e3bb719fdb758915053bee0c7

java/java.go

@@ -1343,13 +1343,10 @@ func LibraryHostFactory() android.Module {
 }
 
 //
-// Java Junit Tests
+// Java Tests
 //
 
 type testProperties struct {
-	// If true, add a static dependency on the platform junit library.  Defaults to true.
-	Junit *bool
-
 	// list of compatibility suites (for example "cts", "vts") that the module should be
 	// installed into.
 	Test_suites []string `android:"arch_variant"`
@@ -1381,9 +1378,6 @@ func (j *Test) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 
 func (j *Test) DepsMutator(ctx android.BottomUpMutatorContext) {
 	j.deps(ctx)
-	if BoolDefault(j.testProperties.Junit, true) {
-		ctx.AddDependency(ctx.Module(), staticLibTag, "junit")
-	}
 	android.ExtractSourceDeps(ctx, j.testProperties.Test_config)
 	android.ExtractSourcesDeps(ctx, j.testProperties.Data)
 }