fix(hub): invalid pending query parameter

[kallydev]

Related #265. Fixed an incorrect SQL statement condition.

Only unstake and withdraw transactions can have a pending status. However, since the staking contract currently does not support unstake and withdraw functionalities, there will be no pending transactions.

Statement template

SELECt *
FROM "stake"."transactions"
WHERE "type" IN ('unstake', 'withdraw') AND NOT EXISTS(
    SELECT TRUE
    FROM "stake"."events"
    WHERE "transactions"."id" = "events"."id" AND "events"."type" = 'claimed'
);

type	count
stake	1186
deposit	105