[Django] #36649: Add `|=` merge operator support to `MultiValueDict` and `QueryDict`.

[Django]

#36649: Add `|=` merge operator support to `MultiValueDict` and `QueryDict`.
-----------------------------------------+------------------------------
Reporter: Adam Johnson | Owner: Adam Johnson
Type: New feature | Status: assigned
Component: HTTP handling | Version: dev
Severity: Normal | Keywords:
Triage Stage: Unreviewed | Has patch: 0
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
-----------------------------------------+------------------------------
Per [https://forum.djangoproject.com/t/add-merge-and-update-operator-
support-to-multivaluedict-querydict/43123 forum discussion], add an
`__ior__` method to these classes to make `|=` work, guarding for
mutability in `QueryDict`.
--
Ticket URL: <https://code.djangoproject.com/ticket/36649>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.