chore: end support for ArangoDB 3.8, 3.9, and 3.10

Still keeping the tests for 3.8 for now.

BREAKING CHANGE: ArangoDB 3.8, 3.9 and 3.10 are no longer supported.

.github/workflows/ci.yml

@@ -8,8 +8,6 @@ jobs:
         arango-image:
           [
             "arangodb:3.8",
-            "arangodb:3.9",
-            "arangodb:3.10",
             "arangodb:3.11",
             "arangodb:3.12",
           ]

README.md

@@ -136,12 +136,12 @@ When done, stop the instance with `npm run stop_arangodb`
 
 cruddl currently supports the following versions of ArangoDB:
 
--   3.8
--   3.9
--   3.10
 -   3.11
 -   3.12
 
+ArangoDB 3.8 is still included in the CI tests, but no longer supported officially, and the CI tests
+will be removed in a future minor or patch release.
+
 Starting with ArangoDB 3.12, the default locale for new databases has been changed from `en_US` to
 `en_US_POSIX`. cruddl does not support `en_US_POSIX` at the moment, so you need to change the locale
 to `en_US`. See