Remove old .gitignore entries. NFC (#12936)

.gitignore

@@ -21,12 +21,4 @@ tools/coverage/
 htmlcov/
 coverage.xml
 
-# Files generated by test code (TODO: generate these elsewhere and remove)
-tests/freetype/objs/*.o
-tests/freetype/objs/*.lo
-
-third_party/lzma.js/lzip/*.o
-third_party/lzma.js/lzma-native
-third_party/lzma.js/lzma-native.exe
-
 .DS_Store