fix(dagster): bump dagster dev test polling timeouts 30s -> 60s (#24838)

## Summary
- Bump three 30s polling ceilings to 60s in
`test_dagster_dev_command.py` (`_wait_for_webserver_running`,
`_wait_for_instance_dir_to_be_written`, and the inline queued-run wait
in `test_dagster_dev_command_no_dagster_home`).
- Single flake observed in build
[152637](https://buildkite.com/dagster/internal/builds/152637#019e50a2-9251-41a4-bd6d-ebac7fdab8b1):
`dagster dev` webserver didn't answer `/server_info` within 30s on the
`:pytest: dagster-1-2-cli-tests-3-12` job. Three polling sites in this
file share the same lifecycle (server start → instance dir write →
schedule enqueue); bumping the ceiling on all three reduces overall
flake risk.

## Test plan
- [ ] CI green on this PR
- [ ] Watch the next ~10 master builds for recurrence of the same
timeout

Internal-RevId: 9817ff8bef7692b918fd624852784824a1fad2bd

Author: smackesey

python_modules/dagster/dagster_tests/cli_tests/command_tests/dagster_dev_command_tests/test_dagster_dev_command.py

@@ -127,7 +127,7 @@ def test_dagster_dev_command_no_dagster_home():
                         # Verify the run was queued (so the dagster.yaml was applied)
                         break
 
-                    if time.time() - start_time > 30:
+                    if time.time() - start_time > 60:
                         raise Exception("Timed out waiting for queued run to exist")
 
                     time.sleep(1)
@@ -265,7 +265,7 @@ def _wait_for_webserver_running(dagit_port: int) -> None:
         except:
             print("Waiting for webserver to be ready..")  # noqa: T201
 
-        if time.time() - start_time > 30:
+        if time.time() - start_time > 60:
             raise Exception("Timed out waiting for webserver to serve requests")
 
         time.sleep(1)
@@ -275,7 +275,7 @@ def _wait_for_instance_dir_to_be_written(parent_dir: Path) -> Path:
     # Wait for instance files to exist
     start_time = time.time()
     while True:
-        if time.time() - start_time > 30:
+        if time.time() - start_time > 60:
             raise Exception("Timed out waiting for instance files to exist")
         subfolders = [
             child