[Bug]: 0.14 release broke formatter accepting file arguments

[alexeagle]

What happened?

Due to keith/rules_multirun#44
(and obviously missing integration testing in this repo)

Version

0.14.0 and 0.14.1

How to reproduce

INFO: Running command line: bazel-bin/tools/format/format.bash lint.sh
Traceback (most recent call last):
  File "/private/var/tmp/_bazel_alexeagle/3eecd93732ac7c6f4f360a54a468da50/execroot/_main/bazel-out/darwin_arm64-fastbuild/bin/tools/format/format.bash.runfiles/_main/../rules_multirun~0.7.0/internal/multirun.py", line 91, in <module>
    _main(sys.argv[-1])
  File "/private/var/tmp/_bazel_alexeagle/3eecd93732ac7c6f4f360a54a468da50/execroot/_main/bazel-out/darwin_arm64-fastbuild/bin/tools/format/format.bash.runfiles/_main/../rules_multirun~0.7.0/internal/multirun.py", line 73, in _main
    with open(path) as f:
FileNotFoundError: [Errno 2] No such file or directory: 'lint.sh'

[alexeagle]

The bug is fixed by a rollback, leaving this open for the roll-forward

[hunshcn]

The bug is fixed by a rollback, leaving this open for the roll-forward

it is time

[alexeagle]

Thanks @hunshcn , rolled forward in #182