Push to Gitlab Docker Registry fails from Gitlab Runner environment with X509 Certificate Error

My CI builds on a locally hosted GitlabRunner are failing when it tries to push a docker image to the gitlab registry. The push step hangs, retries many times and then prints the following error message:
" x509: certificate has expired or is not yet valid".

The same push operation succeeds when I do it from a local machine that is not running within the CI environment.

I am not sure where the problem might lie here. Any suggestions?

The job is:

The trace (truncated to show only a small number of retries) is

Running with gitlab-ci-multi-runner 9.3.0 (3df822b)
2 on kk-mbair-1 (35e4da15)
3 Using Shell executor…
4 Running on Krishnas-MacBook-Air.local…
5 Fetching changes…
6 HEAD is now at ec75f1f test push to see if CI build failure is an intermittent issue
7 Checking out ec75f1f7 as master…
8 Skipping Git submodules setup
14 Synchronizing submodule url for ‘polaris-build’
15 git submodule update --init --remote polaris-build 16 warning: redirecting to https://gitlab.com/polaris-common/polaris-build.git/ 17 package push
18 tagging polaris-vcs-service-base as registry.gitlab.com/polaris-common/polaris-build/polaris-vcs-service/polaris-vcs-service-base
19 pushing registry.gitlab.com/polaris-common/polaris-build/polaris-vcs-service/polaris-vcs-service-base
20 The push refers to repository [registry.gitlab.com/polaris-common/polaris-build/polaris-vcs-service/polaris-vcs-service-base]
21 f6d9f62c2ac7: Preparing
22 44d6b8034338: Preparing
23 dab5c69ea567: Preparing
24 b4ed059be9c7: Preparing
25 d29b2325242f: Preparing
26 c4f87accd112: Preparing
27 ee762c22e7fe: Preparing
28 218deec5453a: Preparing
29 07930e7d22be: Preparing
30 cdb3f9544e4c: Preparing
31 c4f87accd112: Waiting
32 ee762c22e7fe: Waiting
33 218deec5453a: Waiting
34 07930e7d22be: Waiting
35 cdb3f9544e4c: Waiting
36 44d6b8034338: Retrying in 5 seconds
37 44d6b8034338: Retrying in 4 seconds
38 b4ed059be9c7: Retrying in 5 seconds
39 44d6b8034338: Retrying in 3 seconds
40 b4ed059be9c7: Retrying in 4 seconds
41 44d6b8034338: Retrying in 2 seconds
42 b4ed059be9c7: Retrying in 3 seconds
43 44d6b8034338: Retrying in 1 second
44 b4ed059be9c7: Retrying in 2 seconds
45 b4ed059be9c7: Retrying in 1 second
46 44d6b8034338: Retrying in 10 seconds
47 44d6b8034338: Retrying in 9 seconds
48 44d6b8034338: Retrying in 8 seconds
49 44d6b8034338: Retrying in 7 seconds
50 44d6b8034338: Retrying in 6 seconds
… many more of these
… and then
x509: certificate has expired or is not yet valid