Prior to this commit, temporary directories in tests were created using
`filepath.Join` and `os.MkdirAll`.
This commit replaces `os.MkdirAll` with `t.TempDir` in tests. The
directory created by `t.TempDir` is automatically removed when the test
and all its subtests complete.
Reference: https://pkg.go.dev/testing#T.TempDir
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
