fix: handle Firefox location on Windows
fix: handle Firefox location on Windows

Currently the task assumes Firefox is located under process.env.PROGRAMFILES
directory. This is not true, as Firefox, being 32-bit on Windows, is located
in process.env["PROGRAMFILES(X86)"]. This commit adds a fallback to the second path,
being forward-compatible in case 64-bit Firefox gets released for Windows.
karma-runner/karma-firefox-launcher,nishant8BITS/karma-firefox-launcher,jamestalmage/karma-firefox-launcher,oyiptong/karma-firefox-launcher,karma-runner/karma-firefox-launcher