Resolve "Update the way of building gnmi target container in Makefile"

Description

Related Issue

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Closes #304

dev_env_data/clab/demo.clab.yaml

@@ -19,18 +19,30 @@ topology:
     client0:
       kind: linux
       image: registry.code.fbi.h-da.de/danet/gnmi-target/ubuntu:develop
+      binds:
+        - ../../artifacts/ssl:/etc/gnmi-target/ssl
+      cmd:
+        start --cert /etc/gnmi-target/ssl/certs/gnmi-target-selfsigned.crt --key /etc/gnmi-target/ssl/private/gnmi-target-selfsigned.key
       mgmt-ipv4: 172.100.0.3
       group: server
 
     client1:
       kind: linux
       image: registry.code.fbi.h-da.de/danet/gnmi-target/ubuntu:develop
+      binds:
+        - ../../artifacts/ssl:/etc/gnmi-target/ssl
+      cmd:
+        start --cert /etc/gnmi-target/ssl/certs/gnmi-target-selfsigned.crt --key /etc/gnmi-target/ssl/private/gnmi-target-selfsigned.key
       mgmt-ipv4: 172.100.0.4
       group: server
 
     client2:
       kind: linux
-      image: registry.code.fbi.h-da.de/danet/gnmi-target/debian:develop
+      image: registry.code.fbi.h-da.de/danet/gnmi-target/ubuntu:develop
+      binds:
+        - ../../artifacts/ssl:/etc/gnmi-target/ssl
+      cmd:
+        start --cert /etc/gnmi-target/ssl/certs/gnmi-target-selfsigned.crt --key /etc/gnmi-target/ssl/private/gnmi-target-selfsigned.key
       mgmt-ipv4: 172.100.0.5
       group: server