Bump version to 3.3.7

Author: waylan

docs/change_log/index.md

@@ -3,7 +3,7 @@ title: Change Log
 Python-Markdown Change Log
 =========================
 
-(under development): version 3.3.7 (a bug-fix release).
+May 5, 2022: version 3.3.7 (a bug-fix release).
 
 * Disallow square brackets in reference link ids (#1209).
 * Retain configured `pygments_style` after first code block (#1240).

markdown/__meta__.py

@@ -26,7 +26,7 @@
 # (1, 2, 0, 'beta', 2) => "1.2b2"
 # (1, 2, 0, 'rc', 4) => "1.2rc4"
 # (1, 2, 0, 'final', 0) => "1.2"
-__version_info__ = (3, 3, 6, 'final', 0)
+__version_info__ = (3, 3, 7, 'final', 0)
 
 
 def _get_version(version_info):