[DOP-23122] Switch KeycloakAuthProvider to async methods #1446

Job	Run time
MySQL tests / Run MySQL tests	7m 16s
Oracle tests / Run Oracle tests	7m 22s
Clickhouse tests / Run Clickhouse tests	8m 1s
SFTP tests / Run SFTP tests	6m 41s
Samba tests / Run Samba tests	8m 0s
MSSQL tests / Run MSSQL tests	6m 43s
HDFS tests / Run HDFS tests	11m 35s
Hive tests / Run Hive tests	7m 40s
Scheduler tests / Run Scheduler tests	5m 15s
S3 tests / Run S3 tests	11m 56s
FTPS tests / Run FTPS tests	6m 44s
FTP tests / Run FTP tests	9m 46s
WebDAV tests / Run WebDAV tests	6m 54s
Unit tests / Run unit tests	3m 40s
Tests done	24s
	1h 47m 57s

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