Unable to include nested object properties in fields and in where condition in lb4

Steps to reproduce

1. Create an entity with nested model.
   Ex : Employee :

{
  empNo: string,
  empName: string,
  deptId: string,
  location: Location{ address1: string, address2:string, locality:string}
}

this.employeeRepository.find({
  fields: {empName: true, departmentId: true, 'location.locality' : true}, 
  where: {'location.locality': {regexp: pattern}}
});

Current Behavior

Not accepting nested object properties to include in select fields or in where condition

Expected Behavior

I should be able to include nested object properties in where or in fields to select ..

Link to reproduction sandbox

not available

Additional information

node -e 'console.log(process.platform, process.arch, process.versions.node)'
win32 x64 12.13.0

npm ls --prod --depth 0 | grep loopback

+-- @loopback/boot@2.1.0
+-- @loopback/context@3.5.0
+-- @loopback/core@2.4.0
+-- @loopback/openapi-v3@3.2.0
+-- @loopback/repository@2.2.0
+-- @loopback/rest@3.3.0
+-- @loopback/rest-crud@0.8.0
+-- @loopback/rest-explorer@2.1.0
+-- @loopback/service-proxy@2.1.0
+-- loopback-connector-mongodb@4.2.0
`-- tslib@1.11.1