Fix hivemind commit in requirements.txt

requirements.txt

@@ -1,4 +1,4 @@
-git+git://github.com/learning-at-home/hivemind
+git+git://github.com/learning-at-home/hivemind@ed42040
 git+git://github.com/learning-at-home/dalle-pytorch@weight-sharing
 transformers>=4.9.2
 tokenizers>=0.10.2
@@ -8,4 +8,4 @@ wandb>=0.10.33
 nltk>=3.6.2
 sentencepiece
 aiohttp
-requests>=2.24.0
+requests>=2.24.0