Bad #! path in apko_run shell wrapper

[anguslees]

rules_apko/apko/private/apko_run.bzl

Lines 24 to 25 in 1d78765

	LAUNCHER_TEMPLATE = """
	#!#!/usr/bin/env sh

Note double #!#!. This causes the script to fail with "external/rules_apko/apko/_apko_run.sh: 11: Bad substitution"

In addition, the """<newline>#!...""" creates a bad newline before the #!.

I think this should be:

LAUNCHER_TEMPLATE = """\
#!/usr/bin/env sh
...
"""