[PATCH v4 3/6] qapi: Add minor typing workaround for 3.6

[John Snow <jsnow@redhat.com>]

Pylint under 3.6 does not believe that Collection is subscriptable at
runtime. It is, making this a Pylint
bug. https://github.com/PyCQA/pylint/issues/2377

They closed it as fixed, but that doesn't seem to be true as of Pylint
2.13.9, the latest version you can install under Python 3.6. 2.13.9 was
released 2022-05-13, about seven months after the bug was closed.

The least-annoying fix here is to just use the more specific type
Sequence, only because it seems to work in 3.6.

Signed-off-by: John Snow <jsnow@redhat.com>
---
 scripts/qapi/expr.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/scripts/qapi/expr.py b/scripts/qapi/expr.py
index 5a1782b57ea..8701351fdfc 100644
--- a/scripts/qapi/expr.py
+++ b/scripts/qapi/expr.py
@@ -33,11 +33,11 @@
 
 import re
 from typing import (
-    Collection,
     Dict,
     Iterable,
     List,
     Optional,
+    Sequence,
     Union,
     cast,
 )
@@ -195,8 +195,8 @@ def check_defn_name_str(name: str, info: QAPISourceInfo, meta: str) -> None:
 def check_keys(value: _JSONObject,
                info: QAPISourceInfo,
                source: str,
-               required: Collection[str],
-               optional: Collection[str]) -> None:
+               required: Sequence[str],
+               optional: Sequence[str]) -> None:
     """
     Ensure that a dict has a specific set of keys.
 
-- 
2.39.0