Increase test coverage

[tdrozdovsky]

Test coverage of each package is expected to be at least 80%.

To create a PR is necessary to increase the coverage of any package, preferably at least 80%, but can be lower.

internal/common/networkhelper
internal/common/resourceutil
internal/controller/configuremgr
internal/controller/discoverymgr/mnedc
internal/controller/discoverymgr/mnedc/client
internal/controller/discoverymgr/wrapper
internal/controller/securemgr/authenticator
internal/controller/servicemgr/executor/androidexecutor
internal/controller/storagemgr/storagedriver
internal/db/bolt/network
internal/orchestrationapi
internal/restinterface/client
internal/restinterface/externalhandler
internal/restinterface/resthelper
internal/restinterface/resthelper/client/httphelper
internal/restinterface/resthelper/client/tlshelper