test: add unit test for admin and cudoMint modules

[tuantran1702]

Test Descriptions

Test for admin module

KeeperTest

Scenario	Withdrawal Amount	Initial Fee Pool Balance	Expected Remaining Fee Pool Balance	Error?
Sufficient funds	30	40	10	false
Insufficient funds	50	40	40	true
Full withdrawal	40	40	0	false
Zero withdrawal	0	40	40	false
Withdraw nothing from empty fee pool	0	0	0	false
Withdraw any amount from empty fee pool	10	0	0	true

MsgServerTest

Name	Sender	Withdraw Amount	CP Balance	Expected Remaining CP Balance	Expected Error
Available community pool: 40, withdraw: 30	Admin	30	40	10	false
Available community pool: 40, withdraw: 50	Admin	50	40	40	true
Available community pool: 40, withdraw: 40	Admin	40	40	0	false
Available community pool: 40, withdraw: 0	Admin	0	40	40	false
Available community pool: 0, withdraw: 0	Admin	0	0	0	false
Available community pool: 30, withdraw 20, not admin	Not Admin	20	30	30	true
Available community pool: 30, withdraw 40, not admin	Not Admin	40	30	30	true

MsgTest

Initiator	To Address	Coins	Expected Error
Valid address	Valid address	123acudos	None
Valid address	Valid address	123acudos,123eth	None
Purposefully long address	Valid address	123acudos	None
Valid address	Purposefully long address	123acudos	None
Empty address	Valid address	123acudos	Invalid sender address (empty address string is not allowed)
Valid address	Empty address	123acudos	Invalid recipient address (empty address string is not allowed)
Valid address	Valid address	0acudos	Invalid coins: Amount cannot be zero
Valid address	Valid address	123acudos,0eth	Invalid coins: 123acudos,0eth (zero amount for ETH)

Test for cudoMint module

KeeperTest

chainID	mintCoins	feeCollectorAccount	expectedBalance
cudos-app	100000acudos, 1000cudosAdmin	fee collector account	100000acudos, 1000cudosAdmin
cudos-app	no coins	fee collector account	0acudos, 0cudosAdmin