Update samples for `google-cloud-speech` to improve usability

[parthea]

An issue was filed in google-cloud-python related to usability issues with the google-cloud-speech sample located here.

Currently there are 2 imports in speech/snippets/transcribe_streaming_v2.py with similar names. SpeechClient and cloud_speech could be confusing to readers as they appear to be similar.

Right now we have

from google.cloud.speech_v2 import SpeechClient
from google.cloud.speech_v2.types import cloud_speech

Instead we could have

from google.cloud.speech_v2 import SpeechClient
from google.cloud.speech_v2.types import cloud_speech as cloud_speech_types

or this could also work

from google.cloud.speech_v2 import SpeechClient
from google.cloud.speech_v2 import StreamingRecognizeRequest
from google.cloud.speech_v2 import RecognitionConfig
from google.cloud.speech_v2 import StreamingRecognizeResponse

[magar51]

I am taking it up

[jping0220]

This problem is being fixed. Let me know if there is any more questions. Thank you!

[iennae]

hey @magar51, apologies I had asked @jping0220 to take a look at this issue last week and she had started working on this already. Please do take a look at her PR and give feedback if you can. Thank you!