pgvector - New upstream version 0.6.0

pgvector has released 0.6.0 and I have pushed a commit to Salsa [1] to
update the Debian package. I'd like to request a review and upload, as
cycles permit.

I'd like to point out that upstream has dropped support for Postgres 11.
I have updated d/pgversions accordingly but I wanted to make sure that I
haven't missed anything else that needs to be updated.

Let me know if anything needs changes.

Thanks,

--Bradford

[1]: https://salsa.debian.org/postgresql/pgvector/-/commit/42adb80a0506074cd0363fd184fdc93bc4d8c14c