Do not throw if the secrets manager is disabled (#16)

* Do not throw if secrets manager is disabled

* Throw error only if the message is provided

Author: brichet

src/manager.ts

@@ -253,7 +253,10 @@ export namespace SecretsManager {
       throw new Error('Secrets manager is locked, check errors.');
     }
     if (isDisabled('jupyter-secrets-manager:manager')) {
-      lock('Secret registry is disabled.');
+      // If the secrets manager is disabled, we need to lock the manager, but not
+      // throw an error, to let the plugin get activated anyway.
+      console.warn('Secrets manager is disabled.');
+      lock();
     }
     if (isDisabled(id)) {
       lock(`Sign error: plugin ${id} is disabled.`);
@@ -293,9 +296,11 @@ namespace Private {
    *
    * @param message - the error message to throw.
    */
-  export function lock(message: string) {
+  export function lock(message?: string): void {
     locked = true;
-    throw new Error(message);
+    if (message) {
+      throw new Error(message);
+    }
   }
 
   /**