drop install FairScale for TPU (#5113)

* drop install FairScale for TPU

* typo

Co-authored-by: Roger Shieh <sh.rog@protonmail.ch>

dockers/base-xla/Dockerfile

@@ -97,6 +97,8 @@ RUN \
     python -c "fname = 'requirements.txt' ; lines = [line for line in open(fname).readlines() if not line.startswith('torch')] ; open(fname, 'w').writelines(lines)" && \
     # drop Horovod as it is not needed
     python -c "fname = 'requirements/extra.txt' ; lines = [line for line in open(fname).readlines() if not line.startswith('horovod')] ; open(fname, 'w').writelines(lines)" && \
+    # drop fairscale as it is not needed
+    python -c "fname = 'requirements/extra.txt' ; lines = [line for line in open(fname).readlines() if 'fairscale' not in line] ; open(fname, 'w').writelines(lines)" && \
     # drop TorchVision as it was installed with XLA
     python -c "fname = 'requirements/examples.txt' ; lines = [line for line in open(fname).readlines() if not line.startswith('torchvision')] ; open(fname, 'w').writelines(lines)" && \
     pip install --requirement ./requirements/devel.txt --upgrade-strategy only-if-needed && \

dockers/tpu-tests/Dockerfile

@@ -27,8 +27,10 @@ COPY ./ ./pytorch-lightning/
 RUN \
     # Install pytorch-lightning at the current PR, plus dependencies.
     #pip install -r pytorch-lightning/requirements.txt --no-cache-dir && \
-    # drop Horovod
+    # drop Horovod as it is not needed
     python -c "fname = 'pytorch-lightning/requirements/extra.txt' ; lines = [line for line in open(fname).readlines() if not line.startswith('horovod')] ; open(fname, 'w').writelines(lines)" && \
+    # drop fairscale as it is not needed
+    python -c "fname = 'pytorch-lightning/requirements/extra.txt' ; lines = [line for line in open(fname).readlines() if 'fairscale' not in line] ; open(fname, 'w').writelines(lines)" && \
     pip install -r pytorch-lightning/requirements/devel.txt --no-cache-dir --upgrade-strategy only-if-needed
 
 #RUN python -c "import pytorch_lightning as pl; print(pl.__version__)"