feat: allow interactive docker testing with 'command' env var

Piping to the 'bash' command does not allow for interacting with the Docker container when running the 'test-docker' make target. By moving it to its own line, the interaction is now allowed. Example: `command=bash make test-docker`

Author: Sam Harrison

.gitignore

@@ -5,7 +5,7 @@ test/config.js
 .env*
 *.log
 .vscode/
-prism
+prism*
 package-lock.json
 yarn.lock
 *.bak

Makefile

@@ -20,4 +20,5 @@ test-integ: test
 
 version ?= lts
 test-docker:
-	curl -s https://raw.githubusercontent.com/sendgrid/sendgrid-oai/master/prism/prism.sh | version=$(version) bash
+	curl -s https://raw.githubusercontent.com/sendgrid/sendgrid-oai/master/prism/prism.sh -o prism.sh
+	version=$(version) bash ./prism.sh