keyvault accesspolicies name requirements conflicts with validation

[onionhammer]

Bicep version
0.2.328

Describe the bug
For resources of type 'Microsoft.KeyVault/vaults/accessPolicies', the name must be 'add', 'remove' or 'replace', but this causes the deployment validation to fail with:

The template resource 'add' for type 'Microsoft.KeyVault/vaults/accessPolicies' at line '1' and column '1237' has incorrect segment lengths. A nested resource type must have identical number of segments as its resource name. A root resource type must have segment length one greater than its resource name.

[onionhammer]

Closing in favor of #836