Allow pulling from multiple branches

### Describe the problem

In our setup we have a branch name (`master`) configured as a symbolic reference to another branch name (`main`) to allow developers to call their branch however they like. Commits pushed to one branch will of course be visible in both branches.

The problem is that the *webhook* (Gitea, in this case) payload sent to Weblate contains a a "ref" member which points to whatever branch name the developer pushed to (example: `"ref": "refs/heads/main"`). Weblate then tries to *match* the branch name to the name specified in the configuration for components and unless the referenced head is found it will NOT update anything.

Basically what happens is that changes pushed to the configured branch (say: `main`) result in Weblate strings being updated while changes pushed to the alias (`master`) result in a `No matching repositories found!` failure.

### Describe the solution you'd like

I'd like to be able to specify multiple branch names for the `source repository branch` so that matches are found whatever alias changes are pushes to.

### Describe alternatives you've considered

_No response_

### Screenshots

_No response_

### Additional context

_No response_