Specify python version with uv sync

Author: dandavison

.github/workflows/ci.yml

@@ -97,7 +97,7 @@ jobs:
           TEMPORAL_TEST_PROTO3: 1
         run: |
           uv add --python 3.9 "protobuf<4"
-          uv sync --all-extras
+          uv sync --all-extras --python 3.9
           poe build-develop
           poe gen-protos
           poe format

README.md

@@ -1544,7 +1544,7 @@ poe test -s --log-cli-level=DEBUG -k test_sync_activity_thread_cancel_caught
 #### Proto Generation and Testing
 
 To allow for backwards compatibility, protobuf code is generated on the 3.x series of the protobuf library. To generate
-protobuf code, you must be on Python <= 3.10, and then run `uv add "protobuf<4"` + `uv sync --all-extras`. Then the
+protobuf code, run `uv add "protobuf<4" --python 3.10` + `uv sync --all-extras --python 3.10`. Then the
 protobuf files can be generated via `poe gen-protos`. Tests can be run for protobuf version 3 by setting the
 `TEMPORAL_TEST_PROTO3` env var to `1` prior to running tests.