help: do not abort topicmatch() because of unimportable extensions
This is alternative workaround to D1198, originally spotted by the earlier
version of the releasenotes extension.
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 4 changes to 4 files
new changesets d326ae2d01ee
updating to branch default
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 4 changes to 4 files
new changesets d326ae2d01ee
updating to branch default
4 files updated, 0 files merged, 0 files removed, 0 files unresolved