docs: Fix a few typos

[timgates42]

There are small typos in:

• doc/rest/reference/coordinator.rst
• doc/rest/reference/mapping.rst
• doc/rest/reference/seqdb.rst
• doc/rest/reference/sqlgraph.rst
• doc/rest/tutorials/compgenomics.rst
• doc/rest/whatsnew.rst
• pygr/nlmsa_utils.py
• tests/runtest.py
• tests/testlib/unittest_extensions.py

Fixes:

• Should read implicitly rather than implicity.
• Should read weird rather than wierd.
• Should read vulnerability rather than vulnerabilty.
• Should read referring rather than refering.
• Should read identifier rather than identfier.
• Should read forward rather than forwad.
• Should read constructor rather than contructor.
• Should read constituting rather than consituting.

Semi-automated pull request generated by
https://github.com/timgates42/meticulous/blob/master/docs/NOTE.md