Update pip requirements to pin kubernetes version to 26.1.0

Change-Id: I1c5ffa2baee938a36ea126b30becbc1e9c7d5885
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/requirements.in b/requirements.in
index bd7abb5..95605f5 100644
--- a/requirements.in
+++ b/requirements.in
@@ -14,7 +14,7 @@
 charset-normalizer
 google-auth<2.18.0
 juju==2.9.44.0
-kubernetes
+kubernetes==26.1.0
 motor
 pyasn1
 pyyaml>6