Add ruff configuration

Apply our standard set of rules from our cockpit projects, and fix some
minor fallout:
```
test/check-application:7:1: I001 [*] Import block is un-sorted or un-formatted
test/check-application:9:119: E501 Line too long (122 > 118 characters)
```

Run ruff in CI to ensure we don't break it.

test/run

@@ -12,3 +12,5 @@ export RUN_TESTS_OPTIONS=--track-naughties
 export LINT=1
 
 make check
+
+ruff check test/check*