ServiceBus: Added property pendingReplicationOperationsCount to GeoDR and Migration

[v-Ajnava]

Description

Added new property pendingReplicationOperationsCount to GeoDR and Migration
Swagger PR link:
Azure/azure-rest-api-specs#3314
Azure/azure-rest-api-specs#3330

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[dsgouda]

LGTM

[dsgouda]

Will merge on CIs passing.