Update packages before running prettier

If `make sure` or `make checkformatting` are the first command that are
run after version update that included prettier, the commands will use
the previous version of prettier.

Makefile

@@ -47,11 +47,11 @@ clean:
 	rm -rf build
 
 .PHONY: format
-format:
+format: node_modules/.uptodate
 	yarn run format
 
 .PHONY: checkformatting
-checkformatting:
+checkformatting: node_modules/.uptodate
 	yarn run checkformatting
 
 .PHONY: sure