chore: prevent dependabot from updating the golang version (#4938)

We manage this one manually.



---

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[Apache 2.0 license]: https://www.apache.org/licenses/LICENSE-2.0

Author: mrgrain

.github/dependabot.yml

@@ -68,6 +68,7 @@ updates:
       - language/go
       - auto-approve
     ignore:
+      - dependency-name: "go" # don't upgrad the golang version
       - dependency-name: github.com/aws/jsii-runtime-go
       - dependency-name: github.com/aws/jsii-runtime-go/*
       - dependency-name: github.com/aws/jsii/jsii-calc/go/*