osd: add pg-upmap-primary to clean_pg_upmaps

osd: add pg-upmap-primary to clean_pg_upmaps

This commit adds handling of pg_upmap_primary to `clean_pg_upmaps`
so invalid mappings are properly removed. Invalid mappings occur
when pools are deleted, the PG size is decreased, or an OSD is
marked down/out.

Test cases cover cases where:
1. PG num is reduced (all pg_upmap_primary mappings should be canceled)
2. An OSD outside of the up set has been mapped as the primary
3. An OSD is marked "out"
4. A mapping is redundant
5. A pool is deleted

Run the unit test with:
$ ninja unittest_osdmap
$ ./bin/unittest_osdmap --gtest_filter=*CleanPGUpmapPrimaries* --debug_osd=10

Fixes: https://tracker.ceph.com/issues/67265
Signed-off-by: Laura Flores <lflores@ibm.com>