### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

When creating base-path-mappings on an API Gateway, there is a special `(none)` path when you don't specify a path during creation. Localstack stores this as `basePath: "(none)"` internally.
When you query to get the base paths, the URLs are escaped by the client (verified in both awscli and terraform) so the basePath is sent as `%28none%29` in the url.
Localstack doesn't appear to be decoding urls and when you attempt to get-base-path-mapping it fails in a string comparison of `(none)` to `%28none%29`.

```shell
> aws --endpoint-url=http://localhost:4566 apigateway get-base-path-mapping --domain-name example.com --base-path "(none)"

An error occurred (NotFoundException) when calling the GetBasePathMapping operation: Base path mapping not found: %28none%29
```

### Expected Behavior

When you attempt to get-base-path-mappings after creating one with the (none) path, it succeeds and returns the mapping.

```
> aws --endpoint-url=http://localhost:4566 apigateway get-base-path-mapping --domain-name example.com --base-path "(none)"

{
    "basePath": "(none)",
    "restApiId": "uyy4c3dsho",
    "stage": "dev"
}
```


### How are you starting LocalStack?

With the `localstack` script

### Steps To Reproduce

#### How are you starting localstack (e.g., `bin/localstack` command, arguments, or `docker-compose.yml`)

    make start

#### Client commands (e.g., AWS SDK code snippet, or sequence of "awslocal" commands)

    awslocal apigateway create-rest-api --name "testgw"
    awslocal apigateway create-base-path-mapping --domain-name example.com --rest-api-id <from output above> --stage dev
    awslocal apigateway get-base-path-mapping --domain-name example.com --base-path "(none)"



### Environment

```markdown
- OS: fedora 34
- LocalStack: latest
```


### Anything else?

https://docs.aws.amazon.com/apigateway/api-reference/link-relation/basepathmapping-by-base-path/
"""Connects the root resource of an api gateway to the given object of an s3 bucket."""
        apigw_client = aws_stack.connect_to_service("apigateway")
        s3_uri = "arn:aws:apigateway:{}:s3:path/{}/{}".format(
            aws_stack.get_region(), bucket_name, file_name
        )
        test_role = "test-s3-role"
        role_arn = aws_stack.role_arn(role_name=test_role)
        resources = apigw_client.get_resources(restApiId=api_id)
        # using 
        root_resource_id = resources["items"][0]["id"]
        apigw_client.put_method(
            restApiId=api_id,
            resourceId=root_resource_id,
            httpMethod=method,
            authorizationType="NONE",
            apiKeyRequired=False,
            requestParameters={},
        )
        apigw_client.put_integration(
            restApiId=api_id,
            resourceId=root_resource_id,
            httpMethod=method,
            type="AWS",
            integrationHttpMethod=method,
            uri=s3_uri,
            credentials=role_arn,
        )
    def connect_api_gateway_to_kinesis(self, gateway_name, kinesis_stream):