Fix typo in Python method name

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Closes #11776

contrib/pyzfs/libzfs_core/test/test_libzfs_core.py

@@ -1062,7 +1062,7 @@ class ZFSTest(unittest.TestCase):
         lzc.lzc_bookmark({})
 
     @skipUnlessBookmarksSupported
-    def test_bookmarks_foregin_source(self):
+    def test_bookmarks_foreign_source(self):
         snaps = [ZFSTest.pool.makeName(b'fs1@snap1')]
         bmarks = [ZFSTest.pool.makeName(b'fs2#bmark1')]
         bmark_dict = {x: y for x, y in zip(bmarks, snaps)}