feat: repository tests, unneeded code removed, fixes

account-query/README.md

account-query/pom.xml

...pa165/banking/application/service/BalanceServiceImpl.java

...in/java/cz/muni/pa165/banking/domain/balance/Balance.java

...banking/domain/balance/repository/BalancesRepository.java

...cz/muni/pa165/banking/domain/transaction/Transaction.java

.../domain/transaction/repository/TransactionRepository.java

...application/controller/BalanceControllerEmployeeTest.java

...5/banking/application/controller/BalanceControllerIT.java

...banking/application/controller/BalanceControllerTest.java

...i/pa165/banking/application/mapper/BalanceMapperTest.java

...5/banking/application/service/BalanceServiceImplTest.java

...ava/cz/muni/pa165/banking/domain/balance/BalanceTest.java

...ing/domain/balance/repository/BalancesRepositoryTest.java

...a165/banking/domain/report/TransactionStatisticsTest.java

...ain/transaction/repository/TransactionRepositoryTest.java

account-query/src/test/resources/application.properties