Fix: `clientSpec` needs to specified for every signature

[arnabghose997]

Closes: https://github.com/hypersign-protocol/hid-node/issues/339

A new type is introduced to handle ClientSpec specific inputs:

message ClientSpec {
    string type = 1;
    string adr036SignerAddress = 2;
}

DID Document Transactions:

The string parameter clientSpec is removed. SignInfo is modified as follows:

message SignInfo {
  string verification_method_id = 1;
  string signature = 2;
  ClientSpec clientSpec = 3;
}

Schema Transactions:

The string parameter clientSpec is replaced with clientSpec of type ClientSpec

Credential Status Transactions:

The string parameter clientSpec is replaced with clientSpec of type ClientSpec

Please refer to proto/ssi/v1 directory for more details.

[arnabghose997]

@Pratap2018 I have updated the generated files here: https://github.com/hypersign-protocol/vue-store/commit/621214099a75cb41379a85d3c597afb8e99d6e4f