Pin development tools

The goal of the job introduced in #453 is to catch issues introduced by
Doctrine packages. Let us avoid suprises caused by development tools by
pinning them, and having dependabot bump the version constraint as
suggested in #475 (comment)

Author: greg0ire

.github/dependabot.yml

@@ -1,5 +1,14 @@
 version: 2
 updates:
+  - package-ecosystem: "composer"
+    directory: "/"
+    schedule:
+      interval: "daily"
+      time: "11:00"
+    open-pull-requests-limit: 10
+    labels:
+      - "Dependencies"
+    versioning-strategy: "increase-if-necessary"
   - package-ecosystem: "github-actions"
     directory: "/"
     schedule:

composer.json

@@ -32,8 +32,8 @@
         "doctrine/mongodb-odm": "^1.3.0 || ^2.0.0",
         "doctrine/orm": "^2.14 || ^3",
         "fig/log-test": "^1",
-        "phpstan/phpstan": "^1.10",
-        "phpunit/phpunit": "^9.6.13 || ^10.4.2",
+        "phpstan/phpstan": "1.12.21",
+        "phpunit/phpunit": "^9.6.13 || 10.5.45",
         "psr/log": "^1.1 || ^2 || ^3",
         "symfony/cache": "^5.4 || ^6.3 || ^7",
         "symfony/var-exporter": "^5.4 || ^6.3 || ^7"