[chore]: add bump build number action

[lukepistrol]

Updates build number and pushes changes to main after a push to main. The pre-release action needs to be run manually.

To update the build number we can use Apple's own avgtool which will automatically change the build number in all targets.

I made the change to only make the pre-release run manually because the changes avgtool makes need to be committed and pushed first.

Later on when deploying releases with an actual version number changed based on tags we could easily create another action workflow for that where we set the version number to the tag value.

Any thoughts on this?

Todo

• [ ] The current solution would trigger an endless loop of increasing the build number.

Resources

• https://medium.com/xcblog/agvtool-automating-ios-build-and-version-numbers-454cab6f1bbe
• https://developer.apple.com/library/archive/qa/qa1827/_index.html

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Closes #890

[bombardier200]

I think this is a good idea for now. Then we switch to actually releases we can do the tagging system like you mentioned