Drop redundant libraries from baseline apexAvailable map

These libraries now set the correct apex_available in their Android.bp
files. Therefore, they do not a separate entry in the baseline
apexAvailable map.

Test: m nothing #passes
Bug: 281077552
Change-Id: Icf6b97c3bcc4bda96eefa14ba6d4bf10614bc378
diff --git a/cc/testing.go b/cc/testing.go
index ced0929..d346739 100644
--- a/cc/testing.go
+++ b/cc/testing.go
@@ -82,6 +82,10 @@
 			sanitize: {
 				never: true,
 			},
+			apex_available: [
+				"//apex_available:anyapex",
+				"//apex_available:platform",
+			],
 		}
 
 		cc_prebuilt_library_static {