Disable //test/config_test:config_test under coverage

[yanavlasov]

//test/config_test:config_test is testing that sample configs are correct and the coverage value of this is close to 0. Config parsing should already be covered by the unit or integration tests.
Fixed a few trivial coverage regressions.
It is likely to go into permafail very soon as the resulting binary is very close to 36Gb limit already

Risk Level: none
Testing: unit tests
Docs Changes: no
Release Notes: no
Platform Specific Features: no

[repokitteh-read-only]

As a reminder, PRs marked as draft will not be automatically assigned reviewers,
or be handled by maintainer-oncall triage.

Please mark your PR as ready when you want it to be reviewed!

🐱

Caused by: #45820 was opened by yanavlasov.

see: more, trace.

[yanavlasov]

Checking if it affects coverage

[yanavlasov]

/coverage

[repokitteh-read-only]

Coverage for this Pull Request will be rendered here:

https://storage.googleapis.com/envoy-cncf-pr/45820/coverage/index.html

For comparison, current coverage on main branch is here:

https://storage.googleapis.com/envoy-cncf-postsubmit/main/coverage/index.html

The coverage results are (re-)rendered each time the CI Envoy/Checks (coverage) job completes.

🐱

Caused by: a #45820 (comment) was created by @yanavlasov.

see: more, trace.

[yanavlasov]

/coverage

[repokitteh-read-only]

Coverage for this Pull Request will be rendered here:

https://storage.googleapis.com/envoy-cncf-pr/45820/coverage/index.html

For comparison, current coverage on main branch is here:

https://storage.googleapis.com/envoy-cncf-postsubmit/main/coverage/index.html

The coverage results are (re-)rendered each time the CI Envoy/Checks (coverage) job completes.

🐱

Caused by: a #45820 (comment) was created by @yanavlasov.

see: more, trace.