### 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/
client = aws_stack.connect_to_service("apigateway")
        apigw_name = "gw-%s" % short_uid()
        test_id = "testId123"
        result = client.create_rest_api(name=apigw_name, tags={TAG_KEY_CUSTOM_ID: test_id})
        self.assertEqual(test_id, result["id"])
        self.assertEqual(apigw_name, result["name"])
        result = client.get_rest_api(restApiId=test_id)
        self.assertEqual(test_id, result["id"])
        self.assertEqual(apigw_name, result["name"])
    def test_api_gateway_kinesis_integration(self):
        
        stream = aws_stack.create_kinesis_stream(self.TEST_STREAM_KINESIS_API_GW)
        stream.wait_for()
        
        result = self.connect_api_gateway_to_kinesis(
            "test_gateway1", self.TEST_STREAM_KINESIS_API_GW
        )
        
        test_data = {
            "records": [