Update google/certificate-transparency-go to v1.0.10

[thaJeztah]

The current vendor was between v1.0.9 and v1.0.10; this
change switches the dependency to use golang/protobuf instead
of gogo/protobuf.

full diff: google/certificate-transparency-go@5ab67e5...v1.0.10

[thaJeztah]

/cc @justincormack @cyli (also see #2689)

[codecov]

Codecov Report

Merging #2688 into master will decrease coverage by 0.1%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2688      +/-   ##
==========================================
- Coverage   61.89%   61.79%   -0.11%     
==========================================
  Files         134      134              
  Lines       21771    21771              
==========================================
- Hits        13476    13453      -23     
- Misses       6836     6867      +31     
+ Partials     1459     1451       -8

[thaJeztah]

Something very odd with vendor check in CI; I tried reproducing it locally, but wasn't able to; wondering if it's an issue in CircleCI (either the config or how tests are run)

[thaJeztah]

Wonder if it's checking from the wrong directory? Something else?

https://github.com/docker/swarmkit/blob/2d27a21b5776827f0918d10db5f62979b7cf2a2b/circle.yml#L53-L55

https://github.com/docker/swarmkit/blob/19114b466a3bf1a538e40d641f809d9d3bf74515/.circleci/config.yml#L72-L77

[cyli]

I have no idea why, but when I ran the CI build with ssh, it looks like vendor directory is missing a lot of code that is in the vendor.bak directory. I'll try to do some more debugging in the morning. I can't replicate locally either.

[cyli]

Update: nm, it's because CircleCI does set the GOPATH variable to something like ~/.go_workspace, so since I set it to something else, I need to set it everywhere.

[thaJeztah]

rebased to get rid of the temporary cherry-pick; this should be good to go now

[cyli]

LGTM