Decimal values in durations are not parsed correctly

[rcjsuen]

FROM alpine
HEALTHCHECK --interval=.1ms CMD l

$ dockerfile-utils lint Dockerfile
$

$ docker build .
Sending build context to Docker daemon  1.695MB
Error response from daemon: Dockerfile parse error line 2: Interval "interval" cannot be less than 1ms

We aren't handling a value of .1ms properly it seems. A value of 0.1ms is correctly flagged as an error though.

$ dockerfile-utils lint Dockerfile.1
Line: 2
HEALTHCHECK --interval=0.1ms CMD l
              ^^^^^^^^
Error: Interval "interval" cannot be less than 1ms