fix: Don't install prerelease versions when installing latest

[Copilot]

When users don't specify a version, the action could install prerelease versions because gh release list includes them by default.

Changes

• Added --exclude-pre-releases flag to gh release list command in entrypoint.sh

# Before
TAG=$(gh release list --json tagName --jq '.[].tagName' --repo "knope-dev/knope" | grep knope | head -n 1)

# After  
TAG=$(gh release list --exclude-pre-releases --json tagName --jq '.[].tagName' --repo "knope-dev/knope" | grep knope | head -n 1)

Users explicitly specifying prerelease versions (e.g., version: 1.0.0-rc.1) are unaffected.

Original prompt

Make sure we don't pull prerelease versions if someone asks for latest

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