Revert "Using AAF release Frankfurt dockers"

This reverts commit 306fa85f8e97e1e7f95f8b429088f570f2926d39.
Since this patch, we're seeing a lot of errors on healtchecks and e2e
tests.
Reverting it in order to make master work again.

Issue-ID: AAF-1127
Signed-off-by: Sylvain Desbureaux <sylvain.desbureaux@orange.com>
Change-Id: Ie40559ef5a3da60457b0af306b802e7a81d968be
diff --git a/kubernetes/aaf/charts/aaf-hello/values.yaml b/kubernetes/aaf/charts/aaf-hello/values.yaml
index 786f0b0..aeb6590 100644
--- a/kubernetes/aaf/charts/aaf-hello/values.yaml
+++ b/kubernetes/aaf/charts/aaf-hello/values.yaml
@@ -41,7 +41,7 @@
 
 replicaCount: 0
 
-image: onap/aaf/aaf_hello:2.1.22
+image: onap/aaf/aaf_hello:2.1.20
 
 service:
   name: aaf-hello