Add synthtool scripts (#3765)
Add synthtool scripts (#3765)

* Add assets synth script

* Add automl synth script

* Add BigQueryDataTransfer synth

* Add BigTable synth

* Add BigTableAdmin synth

* Add container synth

* Add containeranalysis synth

* Add dataproc synth

* Add datastore synth

* Add dialogflow synth

* Add dlp synth

* Add errorreporting synth

* Add firestore synth

* Add iot synth

* Add kms synth

* Add language synth

* Add logging synth

* Add monitoring synth

* Add oslogin synth

* Add pubsub synth

* Add redis synth

* Add spanner synth

* Add speech synth

* Add tasks synth

* Add texttospeech synth

* Add trace synth

* Add videointelligence synth

* Add vision synth

* Add websecurityscanner synth

* Add compute synth

* Remove unnecessary import

* Remove compute synth and remove excess logging statements

googleapis/java-tasks,googleapis/java-tasks,googleapis/java-tasks