Make: Speed up make run by removing redundant make go-gen in .bra (#84827)

Make: Remove redundant `make go-gen` in .bra, build-go already calls this
Calling twice really slows down backend build time since wire gets called twice and that uses a few gigs of memory

Author: kylebrandt

.bra.toml

@@ -1,6 +1,5 @@
 [run]
 init_cmds = [
-  ["GO_BUILD_DEV=1", "make", "gen-go"],
   ["GO_BUILD_DEV=1", "make", "build-go"],
   ["make", "gen-jsonnet"],
   ["./bin/grafana", "server", "-packaging=dev", "cfg:app_mode=development"]
@@ -17,7 +16,6 @@ watch_exts = [".go", ".ini", ".toml", ".template.html"]
 ignore_files = [".*_gen.go"]
 build_delay = 1500
 cmds = [
-  ["GO_BUILD_DEV=1", "make", "gen-go"],
   ["GO_BUILD_DEV=1", "make", "build-go"],
   ["make", "gen-jsonnet"],
   ["./bin/grafana", "server", "-packaging=dev", "cfg:app_mode=development"]