Set Subway per-upstream request_timeout_seconds to 90s

Subway's default per-upstream request timeout is 30s. With three Acala
public RPC endpoints, heavy storage queries that take longer than 30s
cause Subway to cycle through all three endpoints (~90s) before any
single upstream has a chance to respond, and the test-side waiting
client times out.

`request_timeout_seconds` was added to `ClientConfig` in
AcalaNetwork/subway#203 (Subway v0.1.1+). Setting it to 90 lets a
single upstream attempt run long enough to complete those queries
instead of being preempted by Subway's own per-endpoint clock.

The companion exclusion of Acala tests in `vitest.config.mts` is
intentionally left in place; this commit only restores Subway's
ability to wait long enough. Lifting the exclusion is a separate
verification step.

Author: rockbmb

.github/subway-template.yml

@@ -7,6 +7,12 @@ extensions:
     # the failover ladder on stall/disconnect via its existing rotation
     # logic, so an initial bias toward array[0] doesn't sacrifice resilience.
     shuffle_endpoints: false
+    # Heavy upstream queries (e.g. Acala storage at the pinned block) can take
+    # longer than Subway's default 30s per-upstream timeout. Without this,
+    # Subway cycles through the entire endpoint list before any single
+    # upstream has a chance to respond. Requires Subway >= v0.1.1
+    # (AcalaNetwork/subway#203).
+    request_timeout_seconds: 90
   event_bus:
   substrate_api:
     stale_timeout_seconds: 180