Try to fix protobuf versions once again (#95)

The goals of these changes are:

- Make Petals work in Colab right after just doing `pip install -r requirements.txt`
- Make tests work independently of the protobuf package version chosen while installing dependencies

examples/prompt-tuning-personachat.ipynb

@@ -42,8 +42,6 @@
     "if IN_COLAB:\n",
     "    subprocess.run(\"git clone https://github.com/bigscience-workshop/petals\", shell=True)\n",
     "    subprocess.run(\"pip install -r petals/requirements.txt\", shell=True)\n",
-    "    subprocess.run(\"pip uninstall -y hivemind\", shell=True)\n",
-    "    subprocess.run(\"pip install git+https://github.com/learning-at-home/hivemind@94c985d2dc7a79a091e46c755e9f2f4469b164c7\", shell=True)\n",
     "    subprocess.run(\"pip install datasets wandb\", shell=True)\n",
     "\n",
     "    try:\n",

examples/prompt-tuning-sst2.ipynb

@@ -42,8 +42,6 @@
     "if IN_COLAB:\n",
     "    subprocess.run(\"git clone https://github.com/bigscience-workshop/petals\", shell=True)\n",
     "    subprocess.run(\"pip install -r petals/requirements.txt\", shell=True)\n",
-    "    subprocess.run(\"pip uninstall -y hivemind\", shell=True)\n",
-    "    subprocess.run(\"pip install git+https://github.com/learning-at-home/hivemind@94c985d2dc7a79a091e46c755e9f2f4469b164c7\", shell=True)\n",
     "    subprocess.run(\"pip install datasets wandb\", shell=True)\n",
     "\n",
     "    try:\n",

requirements.txt

@@ -3,6 +3,6 @@ bitsandbytes==0.34.0
 accelerate==0.10.0
 huggingface-hub==0.7.0
 transformers==4.21.3
-protobuf>=3.12.2,<4.0.0
+protobuf>=3.20.3,<4.0dev
 git+https://github.com/learning-at-home/hivemind@1e4af434f35ad43208e7e5df569c5ff5eb79681b
 humanfriendly