Update Speech generated client documentation and REST configuration.

[yoshi-automation]

This PR was generated using Autosynth. 🌈

Here's the log from Synthtool:

synthtool > Cloning googleapis.
synthtool > Running generator for google/cloud/speech/artman_speech_v1.yaml.
synthtool > Ensuring dependencies.
synthtool > Pulling artman image.
synthtool > Generated code into /home/kbuilder/.cache/synthtool/googleapis/artman-genfiles/php/google-cloud-speech-v1.
synthtool > Running generator for google/cloud/speech/artman_speech_v1p1beta1.yaml.
synthtool > Ensuring dependencies.
synthtool > Pulling artman image.
synthtool > Generated code into /home/kbuilder/.cache/synthtool/googleapis/artman-genfiles/php/google-cloud-speech-v1p1beta1.
synthtool > Replaced 'Copyright \\d{4}' in src/V1p1beta1/Gapic/SpeechGapicClient.php.
synthtool > Replaced 'Copyright \\d{4}' in src/V1/Gapic/SpeechGapicClient.php.
synthtool > Replaced 'Copyright \\d{4}' in src/V1p1beta1/Gapic/SpeechGapicClient.php.
synthtool > Replaced 'Copyright \\d{4}' in tests/System/V1p1beta1/SpeechSmokeTest.php.
synthtool > Replaced 'Copyright \\d{4}' in tests/System/V1/SpeechSmokeTest.php.
synthtool > Replaced 'Copyright \\d{4}' in tests/Snippet/V1/SpeechClientTest.php.
synthtool > Replaced 'Copyright \\d{4}' in tests/Unit/V1p1beta1/SpeechClientTest.php.
synthtool > Replaced 'Copyright \\d{4}' in tests/Unit/V1/SpeechClientTest.php.
synthtool > Replaced 'Copyright \\d{4}' in tests/Unit/V1/SpeechClientExtensionTest.php.
synthtool > Replaced 'RecognitionConfig_AudioEncoding' in src/V1p1beta1/Gapic/SpeechGapicClient.php.
synthtool > Replaced 'RecognitionConfig_AudioEncoding' in src/V1/Gapic/SpeechGapicClient.php.
synthtool > Replaced 'will be removed in the next major release' in src/V1p1beta1/StreamingRecognizeResponse_SpeechEventType.php.
synthtool > Replaced 'will be removed in the next major release' in src/V1p1beta1/RecognitionMetadata_InteractionType.php.
synthtool > Replaced 'will be removed in the next major release' in src/V1p1beta1/RecognitionMetadata_RecordingDeviceType.php.
synthtool > Replaced 'will be removed in the next major release' in src/V1p1beta1/RecognitionConfig_AudioEncoding.php.
synthtool > Replaced 'will be removed in the next major release' in src/V1p1beta1/RecognitionMetadata_MicrophoneDistance.php.
synthtool > Replaced 'will be removed in the next major release' in src/V1p1beta1/RecognitionMetadata_OriginalMediaType.php.
synthtool > Replaced 'will be removed in the next major release' in src/V1/StreamingRecognizeResponse_SpeechEventType.php.
synthtool > Replaced 'will be removed in the next major release' in src/V1/RecognitionConfig_AudioEncoding.php.
synthtool > Cleaned up 1 temporary directories.

[googlebot]

Thanks for your pull request. It looks like this may be your first contribution to a Google open source project (if not, look below for help). Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

📝 Please visit https://cla.developers.google.com/ to sign.

Once you've signed (or fixed any issues), please reply here (e.g. I signed it!) and we'll verify it.

---

What to do if you already signed the CLA

Individual signers

• It's possible we don't have your GitHub username or you're using a different email address on your commit. Check your existing CLA data and verify that your email is set on your git commits.

Corporate signers

• Your company has a Point of Contact who decides which employees are authorized to participate. Ask your POC to be added to the group of authorized contributors. If you don't know who your Point of Contact is, direct the Google project maintainer to go/cla#troubleshoot (Public version).
• The email used to register you as an authorized contributor must be the email used for the Git commit. Check your existing CLA data and verify that your email is set on your git commits.
• The email used to register you as an authorized contributor must also be attached to your GitHub account.

[googlebot]

A Googler has manually verified that the CLAs look good.

(Googler, please make sure the reason for overriding the CLA status is clearly documented in these comments.)

[tmatsuo]

@dwsupplee Thanks! Just a note about the PR title by autosynth. We change it appropriately to something that is reflecting the actual change so that our release builder can pick the PR title for the release note :)

[dwsupplee]

Oops! Thanks for the heads up, I'll make sure to update next time :)