Spelling fixes to docs, docstrings, and comments (GH-6374)

diff --git a/Lib/sqlite3/test/dbapi.py b/Lib/sqlite3/test/dbapi.py
index 5332975..7c259d2 100644
--- a/Lib/sqlite3/test/dbapi.py
+++ b/Lib/sqlite3/test/dbapi.py
@@ -161,7 +161,7 @@
             self.cx.in_transaction = True
 
     def CheckOpenWithPathLikeObject(self):
-        """ Checks that we can succesfully connect to a database using an object that
+        """ Checks that we can successfully connect to a database using an object that
             is PathLike, i.e. has __fspath__(). """
         self.addCleanup(unlink, TESTFN)
         class Path: