[roll pigweed] pw_protobuf_compiler: Make the yapf import optional

yapf is a significant requirement and is not essential for proto_repr()
to operate. Gracefully handle missing yapf imports and remove yapf from
install_requires for pw_protobuf_compiler.

Original-Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/100661

https://pigweed.googlesource.com/pigweed/pigweed
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Change-Id: Id1513a927a8d002b217b38adf42abd5138634ad6
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/zephyr-integration/+/100742
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1 file changed
tree: 2f077ce6bc7bbcb65d22902e0b7853f7620c4209
  1. .gitmodules
  2. test.sh