Update .backportrc.json

Author: jwilliams-mongo

.backportrc.json

@@ -2,7 +2,7 @@
     "repoOwner": "mongodb",
     "repoName": "docs-atlas-cli",
 
-    "targetBranchChoices": ["v1.27", "v1.26", "v1.25", "v1.24", "v1.23", "v1.22", "v1.21", "v1.20", "v1.19", "v1.18", "v1.17", "v1.16", "v1.15", "v1.14", "v1.13", "v1.12", "v1.11"],
+    "targetBranchChoices": ["v1.29", "v1.28", "v1.27", "v1.26", "v1.25", "v1.24", "v1.23", "v1.22", "v1.21", "v1.20", "v1.19", "v1.18", "v1.17", "v1.16", "v1.15", "v1.14", "v1.13", "v1.12", "v1.11"],
 
     "editor": "code",
 
@@ -11,4 +11,4 @@
     "backportBranchName": "{{sourcePullRequest.number}}-{{targetBranch}}-backport",
 
     "prTitle": "{{sourcePullRequest.title}}-{{targetBranch}}-backport ({{sourcePullRequest.number}})"
-  }
+  }