Configure dependabot for 1.15.x branch

Signed-off-by: Tommy Ludwig <[email protected]>

Author: shakuzen

.github/dependabot.yml

@@ -68,8 +68,29 @@ updates:
     directory: "/"
     schedule:
       interval: daily
-    target-branch: "main"
+    target-branch: "1.15.x"
     milestone: 277
+    ignore:
+      # metrics are better with https://github.com/Netflix/Hystrix/pull/1568 introduced
+      # in hystrix 1.5.12, but Netflix re-released 1.5.11 as 1.5.18 late in 2018.
+      # <=1.5.11 or 1.5.18 doesn't break with Micrometer, but open metrics won't be correct necessarily.
+      - dependency-name: "com.netflix.hystrix:hystrix-core"
+      # AspectJ does not use semantic versioning, the third number in the version is not the patch version
+      # but it indicates the latest Java version that is supported (the 4th number is the patch version).
+      - dependency-name: "org.aspectj:aspectjweaver"
+        versions: ["[1.9.21,)"]
+      # only upgrade patch versions
+      - dependency-name: "*"
+        update-types:
+          - version-update:semver-major
+          - version-update:semver-minor
+    open-pull-requests-limit: 30
+  - package-ecosystem: gradle
+    directory: "/"
+    schedule:
+      interval: daily
+    target-branch: "main"
+    milestone: 296
     ignore:
       # metrics are better with https://github.com/Netflix/Hystrix/pull/1568 introduced
       # in hystrix 1.5.12, but Netflix re-released 1.5.11 as 1.5.18 late in 2018.