Fix remaining warnings in the test suite

Cabal/tests/PackageTests.hs

Cabal/tests/PackageTests/BenchmarkExeV10/Check.hs

Cabal/tests/PackageTests/BenchmarkOptions/Check.hs

Cabal/tests/PackageTests/BenchmarkStanza/Check.hs

Cabal/tests/PackageTests/BuildDeps/InternalLibrary0/Check.hs

Cabal/tests/PackageTests/BuildDeps/InternalLibrary1/Check.hs

Cabal/tests/PackageTests/BuildDeps/InternalLibrary2/Check.hs

Cabal/tests/PackageTests/BuildDeps/InternalLibrary3/Check.hs

Cabal/tests/PackageTests/BuildDeps/InternalLibrary4/Check.hs

Cabal/tests/PackageTests/PackageTester.hs

Cabal/tests/PackageTests/PathsModule/Executable/Check.hs

Cabal/tests/PackageTests/PathsModule/Library/Check.hs

Cabal/tests/PackageTests/TemplateHaskell/Check.hs

Cabal/tests/PackageTests/TestOptions/Check.hs

Cabal/tests/PackageTests/TestStanza/Check.hs