[auth-swift] Remove module.modulemap as it is unneeded (#10778)

FirebaseAuth.podspec

@@ -46,7 +46,6 @@ supports email and password accounts, as well as several 3rd party authenticatio
     'FirebaseAuth/Interop/*.h',
     'FirebaseAppCheck/Interop/*.h',
   ]
-  s.module_map = source + 'Public/FirebaseAuth/FirebaseAuth.modulemap'
   s.public_header_files = source + 'Public/FirebaseAuth/*.h'
 
   # All headers except the ones in the `Public` should be private.

FirebaseAuth/Sources/Public/FirebaseAuth/FirebaseAuth.modulemap

@@ -1,5 +0,0 @@
-// TODO(ncooke3): Investigate if this file is necessary for the private
-// module map to work.
-framework module FirebaseAuth {
-    umbrella header "FirebaseAuth.h"
-}

scripts/build_private_module_map.rb

@@ -75,7 +75,6 @@ def main(args)
     else
         # Overwrite the private module map with the generated contents.
         File.write(
-            # TODO(ncooke3): See if you can throw it in the public headers directory?
             "#{spec.module_name}/Sources/#{spec.module_name}.private.modulemap",
             private_module_map_contents
         )