Using a custom CA file in corporate environments?

[patcbuilds]

I'm running in a corporate environment where we have a corporate proxy with a custom Certificate Authority file. How can I import this CA file to be used by act? This is a common situation for people working in VPN/Corporate environments with MITM proxies.

I'm using catthehacker/ubuntu:act-latest as my runner.

Here's the error I'm getting when attempting to check out a repo using actions/checkout@v4

❓  ::group::Fetching the repository
| [command]/usr/bin/git -c protocol.version=2 fetch --no-tags --prune --no-recurse-submodules --depth=1 origin +refs/heads/main*:refs/remotes/origin/main* +refs/tags/main*:refs/tags/main*
| fatal: unable to access 'https://github.com/mycorporg/mycorprepo/': server certificate verification failed. CAfile: none CRLfile: none
| The process '/usr/bin/git' failed with exit code 128
| Waiting 18 seconds before trying again
| [command]/usr/bin/git -c protocol.version=2 fetch --no-tags --prune --no-recurse-submodules --depth=1 origin +refs/heads/main*:refs/remotes/origin/main* +refs/tags/main*:refs/tags/main*
| fatal: unable to access 'https://github.com/mycorporg/mycorprepo/': server certificate verification failed. CAfile: none CRLfile: none
| The process '/usr/bin/git' failed with exit code 128
| Waiting 20 seconds before trying again