deploy: fix typo in migrate.yaml

- Remove quotations so that multiple word commands can be invoked.

Change-Id: Ic6f5ed96e45fc7bdca6be805520551dc6fba7c73
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/720404
Auto-Submit: Ethan Lee <ethanalee@google.com>
kokoro-CI: kokoro <noreply+kokoro@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
diff --git a/deploy/migrate.yaml b/deploy/migrate.yaml
index babd5f3..dd5e485 100644
--- a/deploy/migrate.yaml
+++ b/deploy/migrate.yaml
@@ -6,7 +6,9 @@
 
 # Required substitutions
 # _ENV environment (dev, staging, or prod)
-# _CMD command to migrate
+# _CMD command to migrate (e.g., up, down N, force V). IMPORTANT: Do not enclose the command and its arguments in quotes. Enter it as you would on the command line.
+#      Example for force: force 157
+#      Example for up: up
 
 timeout: 1800s
 steps:
@@ -31,7 +33,7 @@
         migrate \
           -source file:../migrations \
           -database "postgres://cloudbuild@127.0.0.1:${port}/${name}?sslmode=disable&password=$$PASSWORD" \
-          "$_CMD"
+          $_CMD
     secretEnv: ['PASSWORD']
 availableSecrets:
   secretManager: