[clang-tidy] Remove extra ";" in ModernizeModuleTest.cpp

Without this fix we get

../../clang-tools-extra/unittests/clang-tidy/ModernizeModuleTest.cpp:270:2: error: extra ';' outside of a function is incompatible with C++98 [-Werror,-Wc++98-compat-extra-semi]
};
 ^
1 error generated.

when compiling with -Werror.