chore: Replace deprecated command with environment file

[jongwooo]

Pull request

What this PR does / why we need it

Update .github/workflows/ci.yaml to use environment file instead of deprecated set-output command.
For more information, see: https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

I found the workflow file that use set-output command through the following command:

$ find . -name '*.yml' -o -name '*.yaml' | xargs egrep '\bset-output\b'

AS-IS

echo ::set-output name=version::$(cat VERSION)

TO-BE

echo "version=$(cat VERSION)" >> $GITHUB_OUTPUT

Which issue(s) this PR fixes

Fixes #286

Describe testing done for PR

None

Additional information or special notes for your reviewer

None

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