Fix xml-interpolator module reference

[nicolasstucki]

We started having it on in lampepfl but now that we need to update it from type to time
we use the fork in dotty-staging. For some reason this reference was never updated.

[liufengyun]

Note that changing submodule URLs may cause infrastructure problems for existing clones, need to run git submodule sync and then git submodule update.

Can we just use lampepfl/xml-interpolator, and remove dotty-staging/xml-interpolator?

[nicolasstucki]

We cannot use lampepfl/xml-interpolator as we should not add patch branches to that project.

Additionally, this is the only project that currently does not use the scheme we have for every submodule. There is no reason to have an exception.

[liufengyun]

I don't mind creating a fork in dotty-staging, I only worry that (1) the change may create unnecessary hassle in workflow; (2) it creates sync problem between dotty-staging/xml-interpreter and lampepfl/xml-interpreter.

If I remember correctly, we fork projects for community projects when we don't have control. In the long run, the forks will diminish.

[nicolasstucki]

It is not only for control. It is also to have a project where we can create any change without polluting the main project while not having our own forks. We have done the mistake of creating branches lampepfl/xml-interpolator which needs to be cleaned up now.

If we only had lampepfl/xml-interpolator we should each fork it. This would be much more complicated than only having dotty-staging/xml-interpolator.

[nicolasstucki]

Because of the past mistake, we now have 17 extra branches that should be removed in https://github.com/lampepfl/xml-interpolator/branches. These need to be cleaned up.

[smarter]

These need to be cleaned up.

Note that we cannot remove any commit which is referenced by a past version of dotty.

[nicolasstucki]

At least we can stop adding more random branches now

[nicolasstucki]

Note that we cannot remove any commit which is referenced by a past version of dotty.

Strong argument for having them in dotty-staging. There we can keep all the branches we want without polluting the project.

[nicolasstucki]

These need to be cleaned up.

Note that we cannot remove any commit which is referenced by a past version of dotty.

All those branches have been merged at some point. I will make a backup in dotty-staging/xml-interpolator of each extra branch, then check that all commits are in lamp/xml-interpolator/master and if so delete the branch.

[anatoliykmetyuk]

Note that we cannot remove any commit which is referenced by a past version of dotty.

In practice, we do not need these commits for versions of Dotty lower than the current RC. This is because the only place we need them is when promoting RC to a stable version. Doing so invokes community tests which can get confused if they don't find the commit we deleted. Nobody runs the tests for commits other than during such a promotion.

All those branches have been merged at some point. I will make a backup in dotty-staging/xml-interpolator of each extra branch, then check that all commits are in lamp/xml-interpolator/master and if so delete the branch.

Note that the hashes of the commits change on any push that cannot be executed without --force. E.g. if you rebase before merging, you'll end up with the same commits but with different hashes. This situation will confuse versions of Dotty that point to a commit by its hash prior to it being rebased.