AWS::Athena::NamedQuery - QueryUri

## 1. Title
#### AWS::Athena::NamedQuery-QueryUri

## 2. Scope of request

#### AWS::Athena::NamedQuery-QueryUri to be able to reference the location of a query file (typically a .sql) rather than having the full query in the cloudformation file

Right now we have to rely on AWS::Athena::NamedQuery-QueryString and have the full query live in the cloudformation file, which can typically span quite a few lines and distract from the core infrastructure logic of cloudformation.
## 3. Expected behavior

#### Support for an Amazon S3 URI or local file path

What would be ideal is to have support for a `QueryUri` parameter in the same fashion than the [CodeUri support in AWS::Serverless::Function](https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-resource-function.html#sam-function-codeuri).

## 4. Suggest specific test cases

#### It should correctly retrieve the sql query from the file location and inject it in the cloudformation template

## 5. Helpful Links to speed up research and evaluation

#### Current QueryString parameter: https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-athena-namedquery.html#cfn-athena-namedquery-querystring
#### CodeUri support in Lambda: https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-resource-function.html#sam-function-codeuri

## 6. Category (required) - Will help with tagging and be easier to find by other users to +1

7. Analytics (Athena, EMR, Glue,...)

## 7. Any additional context (optional)