downgrade wandb on JetPack 4

packages/nemo/Dockerfile.jp4

@@ -22,9 +22,12 @@ ARG SKLEARN_ALLOW_DEPRECATED_SKLEARN_PACKAGE_INSTALL=True
 # Cannot uninstall 'PyYAML'. It is a distutils installed project...
 RUN pip3 install --ignore-installed --upgrade --no-cache-dir --verbose PyYAML
 
-# install sentencepiece
+# install sentencepiece (checkout 635fe84 - previous commit to 8cbdf13)
+# https://github.com/google/sentencepiece/commit/8cbdf13794284c30877936f91c6f31e2c1d5aef7
+# src/sentencepiece/sentencepiece_wrap.cxx:3396:54: error: no matching function for call to 'atomic_fetch_add(std::atomic<long unsigned int>*, int)'
 RUN git clone https://github.com/google/sentencepiece && \
 	cd sentencepiece && \
+	git checkout 635fe84 && \
 	mkdir build && \
 	cd build && \
 	cmake .. && \
@@ -71,6 +74,10 @@ RUN pip3 install --no-cache-dir --verbose "$(find /opt -name 'nemo*.whl' | head
 # cannot allocate memory in static TLS block
 ENV LD_PRELOAD=/usr/local/lib/python3.6/dist-packages/sklearn/__check_build/../../scikit_learn.libs/libgomp-d22c30c5.so.1.0.0
 
+# pytorch_lightning => import wandb.sdk.lib.json_util as json
+# AttributeError: module 'wandb' has no attribute 'sdk'
+RUN pip3 install --no-cache-dir --verbose 'wandb<0.15.8'
+
 # make sure it loads
 RUN pip3 show nemo_toolkit && python3 -c 'import nemo; print(nemo.__version__)'