net/cloudflared: update 2023.2.1 to 2023.8.0
while here: * no longer pin-point the version of go we use to build it; * add '-extldflags "-static"' to GO_BUILDFLAGS; changes and full diff between versions: * https://github.com/cloudflare/cloudflared/blob/2023.8.0/CHANGES.md * https://github.com/cloudflare/cloudflared/compare/2023.2.1...2023.8.0