Bazel CI: Flip --incompatible_remap_main_repo broke many projects in downstream

[meteorcloudy]

https://buildkite.com/bazel/bazel-at-head-plus-downstream/builds/1281

Culprit finder points to 81b57d6
https://buildkite.com/bazel/culprit-finder/builds/236
https://buildkite.com/bazel/culprit-finder/builds/235

[meteorcloudy]

Ping @aehlig , Should we revert the flip or disable all broken downstream projects?
/cc @dslomov

[aehlig]

Ping @aehlig , Should we revert the flip or disable all broken downstream projects?

For rules_go I'm pretty sure the breakage is due to the implicit assumption in that repository that every artifact path generated by bazel starts with external/. So there, it is the downstream project at fault.

For rules_rust I still haven't managed to find out what the root cause of this breakage is. So I still cannot tell, if flag flip uncovered a bug in rules_rust or in bazel (but, on the other hand, #3115 and #7180 are bugs in bazel as well).

[laurentlb]

If project maintainers should fix the code or take a look at the issue, please file bugs.

[aehlig]

Filed issue for rules_go. Again, for rules_rust it is not clear in which code (bazel or rules_rust) the underlying issue is.

[aehlig]

Corresponding issues and/or pull requests have been filed.