Adding 4.2.x branches

Signed-off-by: Ryan Baxter <ryan.baxter@broadcom.com>

Author: ryanjbaxter

.github/dependabot.yml

@@ -15,6 +15,11 @@ updates:
     target-branch: "4.1.x"
     schedule:
       interval: "weekly"
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    target-branch: "4.2.x"
+    schedule:
+      interval: "weekly"
   - package-ecosystem: "github-actions"
     directory: "/"
     target-branch: "main"
@@ -53,6 +58,17 @@ updates:
         update-types:
           - version-update:semver-major
           - version-update:semver-minor
+  - package-ecosystem: maven
+    directory: /
+    schedule:
+      interval: daily
+    target-branch: 4.2.x
+    ignore:
+      # only upgrade patch versions for maintenance branch
+      - dependency-name: "*"
+        update-types:
+          - version-update:semver-major
+          - version-update:semver-minor
   - package-ecosystem: maven
     directory: /
     schedule:
@@ -78,3 +94,8 @@ updates:
     directory: /docs
     schedule:
       interval: weekly
+  - package-ecosystem: npm
+    target-branch: 4.2.x
+    directory: /docs
+    schedule:
+      interval: weekly