Fix removing gRPC from Dockerfile (#173)

The previous fix
(#172)
was not working as deleting the files after installation caused dangling
dependencies - the instrumentation expected a dependency, but it was not
found, causing instrumentation to fail.

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Dockerfile

@@ -9,16 +9,14 @@ WORKDIR /operator-build
 
 ADD aws-opentelemetry-distro/ ./aws-opentelemetry-distro/
 
-RUN mkdir workspace && pip install --target workspace ./aws-opentelemetry-distro
-
 # Remove opentelemetry-exporter-otlp-proto-grpc and grpcio, as grpcio has strict dependencies on the Python version and
 # will cause confusing failures if gRPC protocol is used. Now if gRPC protocol is requested by the user, instrumentation
 # will complain that grpc is not installed, which is more understandable. References:
 # * https://github.com/open-telemetry/opentelemetry-operator/blob/b5bb0ae34720d4be2d229dafecb87b61b37699b0/autoinstrumentation/python/requirements.txt#L2
 # * https://github.com/MicrosoftDocs/azure-docs/blob/main/articles/azure-functions/recover-python-functions.md#troubleshoot-cannot-import-cygrpc
-ENV PYTHONPATH=/operator-build/workspace
-RUN pip uninstall opentelemetry-exporter-otlp-proto-grpc -y
-RUN pip uninstall grpcio -y
+RUN sed -i "/opentelemetry-exporter-otlp-proto-grpc/d" ./aws-opentelemetry-distro/pyproject.toml
+
+RUN mkdir workspace && pip install --target workspace ./aws-opentelemetry-distro
 
 FROM public.ecr.aws/amazonlinux/amazonlinux:minimal