Prefer `type(x) is int` to `isinstance(x, int)` (#14945)

* Perfer `type(x) is int` to `isinstance(x, int)`

This covered all additional instances I could see where `x` was
user-controlled.
The remaining cases are

```
$ rg -s 'isinstance.*[^_]int'
tests/replication/_base.py
576:        if isinstance(obj, int):

synapse/util/caches/stream_change_cache.py
136:        assert isinstance(stream_pos, int)
214:        assert isinstance(stream_pos, int)
246:        assert isinstance(stream_pos, int)
267:        assert isinstance(stream_pos, int)

synapse/replication/tcp/external_cache.py
133:        if isinstance(result, int):

synapse/metrics/__init__.py
100:        if isinstance(calls, (int, float)):

synapse/handlers/appservice.py
262:        assert isinstance(new_token, int)

synapse/config/_util.py
62:        if isinstance(p, int):
```

which cover metrics, logic related to `jsonschema`, and replication and
data streams. AFAICS these are all internal to Synapse

* Changelog

1 files changed, 2 insertions, 2 deletions

diff --git a/synapse/events/validator.py b/synapse/events/validator.py

index a6f0104396..fb1737b910 100644
--- a/synapse/events/validator.py
+++ b/synapse/events/validator.py
@@ -139,7 +139,7 @@ class EventValidator:
         max_lifetime = event.content.get("max_lifetime")
 
         if min_lifetime is not None:
-            if not isinstance(min_lifetime, int):
+            if type(min_lifetime) is not int:
                 raise SynapseError(
                     code=400,
                     msg="'min_lifetime' must be an integer",
@@ -147,7 +147,7 @@ class EventValidator:
                 )
 
         if max_lifetime is not None:
-            if not isinstance(max_lifetime, int):
+            if type(max_lifetime) is not int:
                 raise SynapseError(
                     code=400,
                     msg="'max_lifetime' must be an integer",