Update docs/_docs/reference/contextual/extension-methods.md

Author: odersky

docs/_docs/reference/contextual/extension-methods.md

@@ -247,7 +247,7 @@ The following two rewritings are tried in order:
  1. The selection is rewritten to `m[Ts](e)` and typechecked, using the following
     slight modification of the name resolution rules:
 
-  - If `m` is imported by several imports which are all on the nesting level,
+  - If `m` is imported by several imports which are all on the same nesting level,
     try each import as an extension method instead of failing with an ambiguity.
     If only one import leads to an expansion that typechecks without errors, pick
     that expansion. If there are several such imports, but only one import which is