Make clippy task an allowed failure on Travis
Make clippy task an allowed failure on Travis

It has gotten too flaky to gate a PR on.

Signed-off-by: mulhern <7b51bcf507bcd7afb72bf8663752c0ddbeb517f6@redhat.com>

mulkieran/stratisd,trgill/stratisd,stratis-storage/stratisd,stratis-storage/stratisd,stratis-storage/stratisd,mulkieran/stratisd,trgill/stratisd