Fixed Endpoint View permissions

[Coduz]

This PR fixes the permission and checks required to show the Endpoint View on console which should be available only to admin account, and only if the selected account is the root account or one of the first level accounts.

Related Issue
This PR fixes changes made in #3560 which was wrong due to misleading GwtSession.getRootAccountId() method.

Description of the solution adopted

• Cleaned up GwtSession class
• Deprecated GwtSession.getRootAccountId() and GwtSession.getRootAccountName()
• Fixed the behaviour adding few methods to check the level of the selected Account

Screenshots
None

Any side note on the changes made
None

[codecov]

Codecov Report

Merging #3660 (11e9883) into develop (d3fa400) will decrease coverage by 4.43%.
The diff coverage is n/a.

❗ Current head 11e9883 differs from pull request most recent head 53a0f36. Consider uploading reports for the commit 53a0f36 to get more accurate results

@@              Coverage Diff              @@
##             develop    #3660      +/-   ##
=============================================
- Coverage      48.03%   43.60%   -4.44%     
+ Complexity       259      184      -75     
=============================================
  Files           1686     1686              
  Lines          32165    32165              
  Branches        2642     2642              
=============================================
- Hits           15452    14027    -1425     
- Misses         15806    17332    +1526     
+ Partials         907      806     -101     

Impacted Files	Coverage Δ
...pse/kapua/kura/simulator/GatewayConfiguration.java	0.00% <0.00%> (-100.00%)	⬇️
...a/kura/simulator/birth/BirthCertificateModule.java	0.00% <0.00%> (-100.00%)	⬇️
...ration/exception/KapuaConfigurationErrorCodes.java	0.00% <0.00%> (-100.00%)	⬇️
...del/query/predicate/ChannelMatchPredicateImpl.java	0.00% <0.00%> (-100.00%)	⬇️
...ent/packages/message/internal/PackageResource.java	0.00% <0.00%> (-100.00%)	⬇️
...kages/model/internal/DevicePackageOptionsImpl.java	0.00% <0.00%> (-100.00%)	⬇️
...l/setting/PackageManagementServiceSettingKeys.java	0.00% <0.00%> (-100.00%)	⬇️
...oad/internal/DevicePackageDownloadOptionsImpl.java	0.00% <0.00%> (-100.00%)	⬇️
...lator/app/deploy/DeploymentPackageInformation.java	0.00% <0.00%> (-93.75%)	⬇️
...internal/DeviceManagementOperationCreatorImpl.java	0.00% <0.00%> (-92.86%)	⬇️
... and 110 more