Renaming _patch_properties->_patch_property and accepting key, value.

* docs(samples): add read table snippet

* remove snippet as it already exists

The motivation for this is to prevent a breaking change in a library that has already been made GA: texttospeech googleapis/python-texttospeech#99. The TTS protos have a field named [`input`](https://github.com/googleapis/googleapis/blob/eabe7c0fde64b1451df6ea171b2009238b0df07c/google/cloud/texttospeech/v1/cloud_tts.proto#L134-L143).

Dialogflow CX beta appears to also have a field named `input`, but those changes have not yet been published and it is a pre-GA API.

https://github.com/search?l=Python&p=1&q=org%3Agoogleapis+input_&type=Code

🤖 I have created a release \*beep\* \*boop\* 
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### [0.40.12](https://www.github.com/googleapis/gapic-generator-python/compare/v0.40.11...v0.40.12) (2021-02-26)


### Bug Fixes

* exclude 'input' from reserved names list ([#788](https://www.github.com/googleapis/gapic-generator-python/issues/788)) ([da2ff71](https://www.github.com/googleapis/gapic-generator-python/commit/da2ff717b82357359baeeafad9a3e48a70e194cb))
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This PR was generated with [Release Please](https://github.com/googleapis/release-please). See [documentation](https://github.com/googleapis/release-please#release-please).

…[autoapprove] (#788)

* chore(python): exclude path in renovate.json [autoapprove]

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Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-python:latest@sha256:562802bfac02e012a6ac34eda282f81d06e77326b82a32d7bbb1369ff552b387

* 🦉 Updates from OwlBot post-processor

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* tests: pass '*session.posargs' for systests

Permits running single tests, debugging on errors, etc.

* fix: typos