docs: orthographic fix in comments (#7835)

"seperate" -> "separate".

lib/query-interface.js

@@ -847,7 +847,7 @@ class QueryInterface {
       throw new Error('Unable to set autocommit for a transaction without transaction object!');
       throw new Error('Unable to set autocommit for a transaction without transaction object!');
     }
     }
     if (transaction.parent) {
     if (transaction.parent) {
-      // Not possible to set a seperate isolation level for savepoints
+      // Not possible to set a separate isolation level for savepoints
       return Promise.resolve();
       return Promise.resolve();
     }
     }
 
 
@@ -870,7 +870,7 @@ class QueryInterface {
     }
     }
 
 
     if (transaction.parent || !value) {
     if (transaction.parent || !value) {
-      // Not possible to set a seperate isolation level for savepoints
+      // Not possible to set a separate isolation level for savepoints
       return Promise.resolve();
       return Promise.resolve();
     }
     }