PyYAML bug workaround

Change-Id: I077c3be37489047b7705eaa951f96f56fda4907e
Signed-off-by: Mark Beierl <mark.beierl@canonical.com>
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 64a1b2c..164a562 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -50,7 +50,7 @@
     # via
     #   -r https://osm.etsi.org/gitweb/?p=osm/common.git;a=blob_plain;f=requirements.txt;hb=paas
     #   temporalio
-pyyaml==5.4.1
+pyyaml==5.3.1
     # via -r https://osm.etsi.org/gitweb/?p=osm/common.git;a=blob_plain;f=requirements.txt;hb=paas
 six==1.16.0
     # via