ref: use concrete dict in HC payloads (#73744)

JSONField can serialize only exactly `dict` and not `Mapping`

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src/sentry/auth/services/auth/model.py

@@ -192,7 +192,7 @@ class RpcAuthProvider(RpcModel):
     organization_id: int = -1
     provider: str = ""
     flags: RpcAuthProviderFlags = Field(default_factory=lambda: RpcAuthProviderFlags())
-    config: Mapping[str, Any]
+    config: dict[str, Any]
     default_role: int = -1
     default_global_access: bool = False
 
@@ -218,7 +218,7 @@ class RpcAuthIdentity(RpcModel):
     user_id: int = -1
     auth_provider_id: int = -1
     ident: str = ""
-    data: Mapping[str, Any] = Field(default_factory=dict)
+    data: dict[str, Any] = Field(default_factory=dict)
     last_verified: datetime.datetime = Field(default_factory=datetime.datetime.now)