Run the test suite without -v so a failure shows in the build log (closes #414)

The Docker build cuts each step's log off at 2 MiB. script/test ran
go test -v, whose output for the whole suite passed that limit before
any failure was printed, so a red build showed no failing test. Without
-v, go test prints one result line per package and, for a package that
fails, everything its tests wrote, application log lines included.
-race and the 90s per-package timeout are unchanged.

Model: opus-5-5

script/test

@@ -30,7 +30,8 @@
 #
 # No -v: the Docker build cuts each step's log off at 2 MiB, and verbose output
 # from the whole suite passes that before a failure is printed. Without it, go
-# test prints only the output of failing tests and one result line per package.
+# test prints one result line per package and, for a package that fails,
+# everything its tests wrote, application log lines included.
 set -eu
 
 ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"