fix(http): corrects protocol check for wget availability (eficode#82)

Previously, the script was checking for the wrong PROTOCOL key when checking whether the required tools were available. As a result, it wouldn't detect when `wget` was not present.

wait-for

@@ -55,7 +55,7 @@ wait_for() {
         exit 1
       fi
       ;;
-    wget)
+    http)
       if ! command -v wget >/dev/null; then
         echoerr 'wget command is missing!'
         exit 1