[BREAKING] - remove is_deleted for Connection model #965

Job	Run time
Clickhouse tests / Run Clickhouse tests	1m 23s
Hive tests / Run Hive tests	1m 24s
HDFS tests / Run HDFS tests	1m 24s
MSSQL tests / Run MSSQL tests	1m 25s
MySQL tests / Run MySQL tests	1m 23s
Oracle tests / Run Oracle tests	1m 23s
S3 tests / Run S3 tests	1m 23s
Unit tests / Run unit tests	1m 33s
Scheduler tests / Run Scheduler tests	1m 25s
Tests done	1s
	12m 44s

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