sql: increase timeout for inspect tests

The `sql/inspect.TestInspectMetrics` test was flaking in CI. Increasing
the size will increase the timeout.

Epic: none
Fixes: #156197
Fixes: #156082

Release note: None

Author: bghal

pkg/sql/inspect/BUILD.bazel

@@ -68,6 +68,7 @@ go_library(
 
 go_test(
     name = "inspect_test",
+    size = "large",
     srcs = [
         "index_consistency_check_test.go",
         "inspect_job_test.go",