[GPII-4057]: Lock gem versions with bundler

[natarajaya]

This is a follow-up on gpii-ops/gpii-infra#472.
This also bumps Stackdriver gems to latest versions.

[amatas]

LGTM

[mrtyler]

LGTM

I guess this should go to upstream as well.

FYI in case it comes up: I've had trouble with these google gems in the past: https://github.com/gpii-ops/gpii-infra/blob/master/shared/rakefiles/tests/Gemfile#L11

[stepanstipl]

Thanks for doing this @natarajaya, LGTM.

I think you'll need a new version, 0.9.3 has already been used in #66.

Note: I noticed this adds another 30M to our (already huge ;() exekube image:

gpii/exekube                             0.9.3-google_gpii.0      986f196442d5        26 hours ago        1.17GB
# image from this PR
gpii-ops/exekube                         gems                     516408248f3f        2 hours ago         1.2GB

I guess this should go to upstream as well.

@mrtyler given upstream does not have Ruby at all... how?

[mrtyler]

Oops, I forgot that ruby is only for us. Ignore the request to upstream.

[natarajaya]

Thanks for reviews!

FYI in case it comes up: I've had trouble with these google gems in the past

@mrtyler Nice catch! Since we bundle gems in exekube now, I had to add rspec into separate group and remove gemfiles from gpii-infra.