Fix GHA deprecation of the ::set-output function (#615)

* Fix GHA deprecation of the ::set-output function

https://github.com/fluent/helm-charts/actions/runs/15448780655/job/43485353387?pr=614#step:6:17
https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

Signed-off-by: Asher Foa <asher@asherfoa.com>

* Update .github/workflows/lint-test.yaml

Co-authored-by: Steve Hipwell <steve.hipwell@gmail.com>
Signed-off-by: Asher Foa <asher@userclouds.com>

---------

Signed-off-by: Asher Foa <asher@asherfoa.com>
Signed-off-by: Asher Foa <asher@userclouds.com>
Co-authored-by: Steve Hipwell <steve.hipwell@gmail.com>

Author: asherf

.github/workflows/lint-test.yaml

@@ -31,7 +31,7 @@ jobs:
         run: |
           changed=$(ct list-changed --config ct.yaml)
           if [[ -n "$changed" ]]; then
-            echo "::set-output name=changed::true"
+            echo "changed=true" >> "${GITHUB_OUTPUT}"
           fi
 
       - name: Run chart-testing (lint)