fix: use the built in way for Go to check permissions (fix for Windows and cross platform)

[arizchang1]

instead of explicitly checking EACCES and EPERM, Go has a built in way to check permissions (Windows fix and is cross-platform)

fixes the Windows issue reported by cuzfrog: #938

[evanw]

Do you have a way to reproduce the issue? Ideally changes like this would have test coverage. This is especially important because I don't have a Windows machine and I never use Windows myself.

[arizchang1]

Yes I reproduced it following this #938 (comment)
essentially we can make a dummy directory structure like test/test2/test3/test.ts, where the current user has access to test3 but not test2, and then run esbuild.exe --bundle test.ts from test3. I think it's the same issue that was fixed in that thread, but this is just a better cross-platform way to check permissions