Broken import for Icelandic language data

## How to reproduce the behaviour

It looks like importing language data for Icelandic is broken.
E.g. to get stop words:

```python
# This works
import spacy.lang.en.stop_words
spacy.lang.en.stop_words.STOP_WORDS

# Syntax error in import statement
import spacy.lang.is.stop_words
spacy.lang.is.stop_words.STOP_WORDS
```
Error:
```python
>>> import spacy.lang.is.stop_words
File "", line 1
import spacy.lang.is.stop_words
^
SyntaxError: invalid syntax

```
I have yet to test this on Spacy v3.0.

## Your Environment

* **spaCy version:** 2.3.5
* **Platform:** Linux-5.8.0-53-generic-x86_64-with-glibc2.29
* **Python version:** 3.8.5