This is needed because go and other tools will ignore directories
starting with "_" or "." but would treat a dir called "bin" as a regular
directory.
This in turn meant that when we vendored Go in bin, these tools would by
default scan the whole stdlib included with the bundled vendored go.
See https://pkg.go.dev/cmd/go#hdr-Package_lists_and_patterns for details
Signed-off-by: Ashley Davis <ashley.davis@jetstack.io>