mypy-constrains.txt: bump mypy up to version 1.9

Ceph is still very behind on the version of mypy used in the various
tox test dirs. Bump up to version 1.9 as it only requires a few trivial
fixes to use.

Signed-off-by: John Mulligan <[email protected]>

Author: phlogistonjohn

src/mypy-constrains.txt

@@ -2,7 +2,7 @@
 # Unfortunately this means we have to manually update those 
 # packages regularly. 
 
-mypy==1.1.1
+mypy==1.9
 
 # global
 types-python-dateutil==0.1.3