[Fix]: Prevent back tick escape

[malhotra5]

End-user friendly description of the problem this fixes or functionality that this introduces

• Include this change in the Release Notes. If checked, you must provide an end-user friendly description for your change below

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Give a summary of what the PR does, explaining any non-trivial design decisions

There was an issue of the resolver failing with code blocks in the comment body. This occurred because the backtick in the comment body escapes the variable definition in the workflow. This PR makes sure that the escape cannot occur by setting the variable in the ENV.

Here is a sample workflow log

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Link of any specific issues this addresses
#5892

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To run this PR locally, use the following command:

docker run -it --rm   -p 3000:3000   -v /var/run/docker.sock:/var/run/docker.sock   --add-host host.docker.internal:host-gateway   -e SANDBOX_RUNTIME_CONTAINER_IMAGE=docker.all-hands.dev/all-hands-ai/runtime:b092dd7-nikolaik   --name openhands-app-b092dd7   docker.all-hands.dev/all-hands-ai/openhands:b092dd7

[enyst]

LGTM