Make: package_version less brittle

There is no easy / cross platform way to get at the local crate's
version, so we are doing some grepping, since we can assume grep is
installed on local machines.

This change makes the grep pipeline less brittle by looking for the
`name="quilkin"` block first before grepping for the version details.

Unblocks googleforgames#670

build/Makefile

@@ -29,10 +29,10 @@ rust_toolchain := $(shell grep channel $(project_path)/rust-toolchain.toml | awk
 
 # if this is a release, don't put the sha, otherwise, leave it off.
 ifdef QUILKIN_RELEASE
-	package_version := $(shell grep version -m 1 $(project_path)/Cargo.toml | awk '{print $$3}')
+	package_version := $(shell grep -A1 -w "name = \"quilkin\"" $(project_path)/Cargo.toml | grep version -m 1 | awk '{print $$3}')
 else
 	git_sha := $(shell git rev-parse --short=7 HEAD)
-	package_version := $(shell grep version -m 1 $(project_path)/Cargo.toml | awk '{print $$3}')-${git_sha}
+	package_version := $(shell grep -A1 -w "name = \"quilkin\"" $(project_path)/Cargo.toml | grep version -m 1 | awk '{print $$3}')-${git_sha}
 endif
 
 # Set this value if you want to use an external registry