[RDK-54420] added annotation APIs to Dobby

[goruklu]

Description

Adds "annotate()" and "removeAnnotation()" APIs to Dobby. With this method, key/value pairs can be set for containers at runtime.

Test Procedure

vagrant@dobby-vagrant-focal-arm64:~/srcDobby/build$ DobbyTool annotate sleep12 key1 value1
annotate successful for container 'sleep12'
vagrant@dobby-vagrant-focal-arm64:~/srcDobby/build$ DobbyTool annotate sleep12 key2 value2
annotate successful for container 'sleep12'
vagrant@dobby-vagrant-focal-arm64:~/srcDobby/build$ DobbyTool annotate sleep12 key3 value3
annotate successful for container 'sleep12'
vagrant@dobby-vagrant-focal-arm64:~/srcDobby/build$ DobbyTool annotate sleep12 key2 value5
annotate successful for container 'sleep12'
vagrant@dobby-vagrant-focal-arm64:~/srcDobby/build$ DobbyTool info sleep12
{
 "annotations" :
 {
  "key1" : "value1",
  "key2" : "value5",
  "key3" : "value3"
 },
 "id" : "sleep12",
 "state" : "running",
 "timestamp" : 1319810849810469
}
vagrant@dobby-vagrant-focal-arm64:~/srcDobby/build$ DobbyTool remove-annotation sleep12 key5
removed key5 key from container 'sleep12' annotations
vagrant@dobby-vagrant-focal-arm64:~/srcDobby/build$ DobbyTool info sleep12
{
 "annotations" :
 {
  "key1" : "value1",
  "key2" : "value5",
  "key3" : "value3"
 },
 "id" : "sleep12",
 "state" : "running",
 "timestamp" : 1319841586979048
}
vagrant@dobby-vagrant-focal-arm64:~/srcDobby/build$ DobbyTool remove-annotation sleep12 key2
removed key2 key from container 'sleep12' annotations
vagrant@dobby-vagrant-focal-arm64:~/srcDobby/build$ DobbyTool info sleep12
{
 "annotations" :
 {
  "key1" : "value1",
  "key3" : "value3"
 },
 "id" : "sleep12",
 "state" : "running",
 "timestamp" : 1319852633313708
}

Type of Change

• 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 not work as expected)
• Other (doesn't fit into the above categories - e.g. documentation updates)

Requires Bitbake Recipe changes?

• The base Bitbake recipe (meta-rdk-ext/recipes-containers/dobby/dobby.bb) must be modified to support the changes in this PR (beyond updating SRC_REV)

[ks734]

LGTM