build: fix build failure installing nfpm

Before this fix we used the bin/get-github-release.go script to
install nfpm.

However this script fails scraping the downloads page when the target
has more than a few download options. The alternative would be using
the GitHub API but this needs authentication so as not to be rate
limited on GitHub actions.

This patch switches over to go install which is less efficient but
should work in all circumstances.

Makefile

@@ -96,7 +96,7 @@ build_dep:
 
 # Get the release dependencies we only install on linux
 release_dep_linux:
-	go run bin/get-github-release.go -extract nfpm goreleaser/nfpm 'nfpm_.*_Linux_x86_64\.tar\.gz'
+	go install github.com/goreleaser/nfpm/v2/cmd/nfpm@latest
 
 # Get the release dependencies we only install on Windows
 release_dep_windows: