[chore] Fix deprecations for devfile-resources/devfile-resources.github.io deploy CI

[michael-valdron]

Which area is this issue related to?

/area ci
/area landing-page

Issue Description

There are several upcoming depredations that should be addressed for the landing page/doc pages deployment CI:

1. actions/configure-pages is in need of an update (see Update actions/configure-pages action to v6 devfile-resources/devfile-resources.github.io#25), current version uses Node v20 which is deprecated now, not updating this puts the deploy CI at risk of being disabled
2. set-output command is deprecated and should set the passed values to GITHUB_OUTPUT environment variable instead

Acceptance Criteria

• Provide updates to devfile/devfile-web and/or CI to fix breaking changes in Update actions/configure-pages action to v6 devfile-resources/devfile-resources.github.io#25
• Replace set-output lines with setting GITHUB_OUTPUT to the passed values instead
• Ensure build step passes

Target Odo Version

No response