Created Updating Snapcraft STORE_LOGIN secret (markdown)

Updating-Snapcraft-STORE_LOGIN-secret.md

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+Store Login
+In order to upload to the store, the action requires login credentials. Rather than a user name and password, the action expects the data produced by the snapcraft export-login command.
+
+As well as preventing the exposure of the password, it also allows the credentials to be locked down to only the access the action requires:
+
+$ snapcraft export-login --snaps=PACKAGE_NAME \ --acls package_access,package_push,package_update,package_release \ exported.txt
+
+This will produce a file exported.txt containing the login data, which should be a multi-line file starting with [login.ubuntu.com]. The credentials can be restricted further with the --channels and --expires arguments if desired.
+
+In order to make the credentials available to the workflow, they should be stored as a repository secret:
+
+choose the “Settings” tab.
+choose “Secrets” from the menu on the left.
+click “Add a new secret”.
+set the name to STORE_LOGIN (or whatever is referenced in the workflow), and paste the contents of exported.txt as the value.