Emit unused-import instead of unused-variable when dealing with unused imports

When pylint encounters unused imports in scopes (e.g. functions),
it used to emit `unused-variable`. This is somewhat confusing, as those
names are not necessarily variables, so instead let's emit the more
obvious `unused-import`.

Close #2421

1 files changed, 4 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index c340f8db2..92cbdcf43 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,10 @@ What's New in Pylint 2.2?
 =========================
 
 Release date: TBA
+   * ``pylint`` used to emit a ``unused-variable`` error if unused import was found in the function. Now instead of
+     ``unused-variable``, ``unused-import`` is emitted.
+
+     Close #2421
 
    * Handle asyncio.coroutine when looking for ``not-an-iterable`` check.