Add CODEOWNERS for Diagnostics and OmsAgent
Add CODEOWNERS for Diagnostics and OmsAgent

vityagi/azure-linux-extensions,vityagi/azure-linux-extensions,bpramod/azure-linux-extensions,Azure/azure-linux-extensions,vityagi/azure-linux-extensions,bpramod/azure-linux-extensions,bpramod/azure-linux-extensions,Azure/azure-linux-extensions,bpramod/azure-linux-extensions,vityagi/azure-linux-extensions,vityagi/azure-linux-extensions,vityagi/azure-linux-extensions,bpramod/azure-linux-extensions,vityagi/azure-linux-extensions,bpramod/azure-linux-extensions,Azure/azure-linux-extensions,bpramod/azure-linux-extensions,Azure/azure-linux-extensions,Azure/azure-linux-extensions,Azure/azure-linux-extensions,Azure/azure-linux-extensions