Upgrade to release 2.6.0:
- adexchangebuyer2: update the api
- cloudasset: update the api
- composer: update the api
- compute: update the api
- dfareporting: update the api
- dialogflow: update the api
- displayvideo: update the api
- gkehub: update the api
- healthcare: update the api
- retail: update the api
- sasportal: update the api
- servicedirectory: update the api
- servicemanagement: update the api
- servicenetworking: update the api
- servicenetworking: update the api
- spanner: update the api
Signed-off-by: Leon Anavi <leon.anavi@konsulko.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Trevor Gamblin <trevor.gamblin@windriver.com>
