isabelle: fix ULO namepsace

[kissen]

This patch fixes a typo in the XML namespace in the Isabelle exporter. If you look at the ontology file you see that the XML namespace ends with a hash.

[tkw1536]

LGTM, I think the test failures are not related to the changes introduced.

[tkw1536]

@florian-rabe FYI this is coming from the student working on tetrapodal search.

[kohlhase]

Why has this not been merged? Was this just forgotten?

[florian-rabe]

Which # is it?

Is the # the bug or the fix?

[Jazzpirate]

Which # is it?

Is the # the bug or the fix?

The # is the "bug" - Isabelle uses that (if I remember correctly) as a separator between a name and it's "declaration type"; e.g. "zero#constant", "Nat#type" etc.

[kissen]

Which # is it?
Is the # the bug or the fix?

The # is the "bug" - Isabelle uses that (if I remember correctly) as a separator between a name and it's "declaration type"; e.g. "zero#constant", "Nat#type" etc.

Is that a problem? I believe all this patch changes is the emitted namespace. Any more hashes afterwards in an URIs should not be a problem(?)

The problem from what I understand is just that the namespace that's being emitted is missing the hash, so we get https://mathhub.info/ulofoobar in the XML files, rather than the intended https://mathhub.info/ulo#foobar.