use GitHub's gh tool

[mralusw]

[ Test release in my vim-appimage-tst-upstream fork ]

GitHub's own gh tool comes pre-installed on runner images and obviates the need for some external actions. This reduces dependencies on external repos and (security-wise) avoids passing the GITHUB_TOKEN secret to external code in various states of maintenance.

replace octokit/graphql-action@v2.x with gh api graphql

This action uses the (not just deprecated, but EOL'd since September 2023) Node 16, thus generating warnings; octokit seems to only update Node when GitHub completely pulls the rug (which can be months after a release EOL's). Other warnings are unavoidable due to how query parameters must be passed.

gh is also more flexible so it was possible to simplify logic a bit by writing to $GITHUB_ENV directly from the --jq argument (avoiding re-read / re-parse code).

release using gh release create instead of softprop's action

This doesn't change anything, but also removes an external dependency at no extra complexity cost.

[mralusw]

Force push: accidentally changed release title to vim-appimage:... instead of Vim:...

[chrisbra]

Thanks!