### 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/
value = [] if target is None else [target]
                    common.assign_to_path(subject, path, value=value, delimiter="/")
                target = common.extract_from_jsonpointer_path(subject, path)
                if isinstance(target, list) and not path.endswith("/-"):
                    
                    
                    operation["path"] = "%s/-" % path
            result = apply_patch(subject, [operation], in_place=in_place)
            if not in_place:
                subject = result
            results.append(result)
        except JsonPointerException:
            pass  
        except Exception as e:
            if "non-existent object" in str(e):
                if operation["op"] == "replace":
                    
                    operation["op"] = "add"
                    result = apply_patch(subject, [operation], in_place=in_place)
                    results.append(result)
                    continue
                if operation["op"] == "remove" and isinstance(subject, dict):
                    result = subject.pop(operation["path"], None)
                    results.append(result)
                    continue
            raise
    if return_list:
        return results
    return (results or [subject])[-1]
def import_api_from_openapi_spec(