chore(pack): remove third-party grafana and prometheus tarballs

pack/third_party/grafana-12.2.4.linux-amd64.tar.gz

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:5571a4921d0e8cf38f77a76f33fa5ddc765d74ec755c4e4a453e6bd8dd16ae15
-size 189087443

pack/third_party/prometheus-3.5.1.linux-amd64.tar.gz

@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:cd6aea0ab214b05838470668dfcee7d01a7d91913509a227b00401ca872423f0
-size 121098699