Update version of PyYAML

Change-Id: Ib65a9712db84ea4346fdea11c5554845dc2d52ec
Signed-off-by: Mark Beierl <mark.beierl@canonical.com>
(cherry picked from commit 74c40221f883b7f455ca067bd5cef3b8a40c0972)
diff --git a/requirements.txt b/requirements.txt
index 1690bf4..1cc0804 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -44,7 +44,7 @@
     # via -r requirements.in
 pyrsistent==0.19.3
     # via jsonschema
-pyyaml==5.4.1
+pyyaml==6.0.1
     # via -r requirements.in
 requests==2.30.0
     # via -r requirements.in