Microsoft.Insights workbooks & workbooktemplates declared with incorrect ARM URI

I noticed that the newly-added Microsoft.Insights workbooks & workbooktemplates resource are using "/resourceGroup/" instead of "/resourceGroups/" in the "path" declarations. This is tripping up the https://github.com/Azure/autorest.azureresourceschema extension, and I presume generating SDKs which won't actually work with ARM.

@ericc1103 / @avidhanju since you recently authored changes, would you be able to take a look?

Inspect the newly added Microsoft.Insights workbooks and workbooktemplates resource declarations and their path values. Check how the paths are consumed by the autorest.azureresourceschema extension, correct the singular resourceGroup segment to the ARM resourceGroups form, and verify that the resulting schema or generated SDK paths are valid.

Written by the indexing model from the issue text.