Implement MSC3958: suppress notifications from edits (#14960)

Co-authored-by: Brad Murray <brad@beeper.com>
Co-authored-by: Nick Barrett <nick@beeper.com>

Copy the suppress_edits push rule from Beeper to implement MSC3958.

9415a1284b/rust/src/push/base_rules.rs (L98-L114)

stubs/synapse/synapse_rust/push.pyi

@@ -47,6 +47,7 @@ class FilteredPushRules:
         msc3381_polls_enabled: bool,
         msc3664_enabled: bool,
         msc3952_intentional_mentions: bool,
+        msc3958_suppress_edits_enabled: bool,
     ): ...
     def rules(self) -> Collection[Tuple[PushRule, bool]]: ...