Use servicing template text in backport bot (#38601)

Author: BrennanConroy

.github/workflows/backport.yml

@@ -52,8 +52,48 @@ jobs:
 
           /cc %cc_users%
 
+          # {PR title}
+
+          Summary of the changes (Less than 80 chars)
+
+          ## Description
+
+          {Detail}
+
+          Fixes #{bug number} (in this specific format)
+
           ## Customer Impact
 
-          ## Testing
+          {Justification}
+
+          ## Regression?
+
+          - [ ] Yes
+          - [ ] No
+
+          [If yes, specify the version the behavior has regressed from]
 
           ## Risk
+
+          - [ ] High
+          - [ ] Medium
+          - [ ] Low
+
+          [Justify the selection above]
+
+          ## Verification
+
+          - [ ] Manual (required)
+          - [ ] Automated
+
+          ## Packaging changes reviewed?
+
+          - [ ] Yes
+          - [ ] No
+          - [ ] N/A
+
+          ----
+
+          ## When servicing release/2.1
+
+          - [ ] Make necessary changes in eng/PatchConfig.props