Update cli image for ec to new v0.6 build

This is more significant that the usual digest bump, since we're
moving from v0.5 to v0.6.

Intended for inclusion with RHTAS 1.2.

Ref: https://issues.redhat.com/browse/EC-1135

Author: simonbaird

Dockerfile.clients.rh

@@ -7,7 +7,7 @@ FROM quay.io/securesign/fetch-tsa-certs@sha256:852f883b58759e08ffc7d1eb6aa03b310
 
 # Provides the Trusted Artifact Signer CLI binaries, rekor-cli and ec
 FROM quay.io/securesign/rekor-cli@sha256:bc9ab79a853b7bb4c183f4e2ded84cb40fdc3fb7f41e9f7134058a995bda4d1b as rekor
-FROM registry.redhat.io/rhtas/ec-rhel9:0.5@sha256:3d330b4c742f584be63cf11e451f7822863a5960976a721e18bd8b2e9f1c0038 as ec
+FROM registry.redhat.io/rhtas/ec-rhel9:0.6@sha256:03ed0f7b30a7818cb3c35ccba2f48211a602cd2873f61959b24c93a66b177cb4 as ec
 
 # Provides the Trusted Artifact Signer CLI binaries trillian-createtree and trillian-updatetree
 FROM quay.io/securesign/trillian-createtree@sha256:43da71295323660fd9992e3ba2e2ad63ed9f729dbb42401e041ad02c73da718a as trillian-createtree