Replace references of devel with development in prep for change of branch name

Signed-off-by: Adam Warner <me@adamwarner.co.uk>

.github/dependabot.yml

@@ -7,7 +7,7 @@ updates:
     day: saturday
     time: "10:00"
   open-pull-requests-limit: 10
-  target-branch: devel
+  target-branch: development
   versioning-strategy: increase
   reviewers:
     - "pi-hole/web-maintainers"
@@ -18,7 +18,7 @@ updates:
     day: saturday
     time: "10:00"
   open-pull-requests-limit: 10
-  target-branch: devel
+  target-branch: development
   reviewers:
     - "pi-hole/web-maintainers"
 - package-ecosystem: composer
@@ -28,39 +28,6 @@ updates:
     day: saturday
     time: "10:00"
   open-pull-requests-limit: 10
-  target-branch: development-v6
-  reviewers:
-    - "pi-hole/web-maintainers"
-
-# As above, but for development-v6
-- package-ecosystem: npm
-  directory: "/"
-  schedule:
-    interval: weekly
-    day: saturday
-    time: "10:00"
-  open-pull-requests-limit: 10
-  target-branch: development-v6
-  versioning-strategy: increase
-  reviewers:
-    - "pi-hole/web-maintainers"
-- package-ecosystem: github-actions
-  directory: "/"
-  schedule:
-    interval: weekly
-    day: saturday
-    time: "10:00"
-  open-pull-requests-limit: 10
-  target-branch: development-v6
-  reviewers:
-    - "pi-hole/web-maintainers"
-- package-ecosystem: composer
-  directory: "/"
-  schedule:
-    interval: weekly
-    day: saturday
-    time: "10:00"
-  open-pull-requests-limit: 10
-  target-branch: development-v6
+  target-branch: development
   reviewers:
     - "pi-hole/web-maintainers"