chore: Address PR comments 3

Signed-off-by: Carlos Esteban Lopez <lcarlosesteb@vmware.com>

plugins/auth-backend-module-vmware-cloud-provider/src/authenticator.ts

@@ -58,13 +58,10 @@ export const vmwareCloudAuthenticator = createOAuthAuthenticator<
       );
     }
 
+    const vmwareClaims = ['email', 'given_name', 'family_name', 'context_name'];
+
     const identity = decodeJwt(input.session.idToken);
-    const missingClaims = [
-      'email',
-      'given_name',
-      'family_name',
-      'context_name',
-    ].filter(key => !(key in identity));
+    const missingClaims = vmwareClaims.filter(key => !(key in identity));
 
     if (missingClaims.length > 0) {
       throw new Error(
@@ -72,6 +69,16 @@ export const vmwareCloudAuthenticator = createOAuthAuthenticator<
       );
     }
 
+    const typeMismatchClaims = vmwareClaims.filter(
+      key => typeof identity[key] !== 'string',
+    );
+
+    if (typeMismatchClaims.length > 0) {
+      throw new Error(
+        `ID token claims type mismatch: ${typeMismatchClaims.join(', ')}`,
+      );
+    }
+
     if (identity.context_name !== input.fullProfile.organizationId) {
       throw new Error(`ID token organizationId mismatch`);
     }