Fix coq-metacoq-template.8.17.dev

[liyishuai]

Current failure is caused by:

• coq-8.17 branch no longer builds on ocaml 4.11.2 MetaCoq/metacoq#1022

[liyishuai]

The CI of #2893 should have complained that coq-metacoq-template-pcuic cannot compile. Maybe need a different timeout strategy.

[liyishuai]

Maybe worth merging asynchronously from MetaCoq/metacoq#1023.

[silene]

The CI of #2893 should have complained that coq-metacoq-template-pcuic cannot compile. Maybe need a different timeout strategy.

It did complain. Unfortunately, when there is a timeout, one has to go and read the logs to check whether the timeout is hiding a real compilation error. I suppose we could set the variable RUNNER_SCRIPT_TIMEOUT to something like 150m, so that the cumulative time of before_script and script does not exceed 3 hours, and then have an after_script that checks whether there was an actual compilation failure and reports it more prominently in the logs.

[liyishuai]

Now passes CI.
Propose merging for now, and reverting c292c3b after the compatibility issue gets fixed.