Kerberos not working anymore in 4.9 and 4.10

Describe the bug: It seems while refactoring Dockerfile during Py2/Py3 swap, kerberos support has been accidentially dropped. Following crucial packages are missing since then: krb5-config, krb5-user (see kerberos introduction in #1051 and drop in #1593 )

Steps to reproduce it? enable kerberos and see that kerberos binaries are missing:

FileNotFoundError: [Errno 2] No such file or directory: '/usr/bin/kinit': '/usr/bin/kinit'
[14/Jun/2021 07:03:23 ] supervisor   WARNING  Exit code for /usr/share/hue/build/env/bin/hue kt_renewer: 1
[14/Jun/2021 07:03:23 ] supervisor   ERROR    Process /usr/share/hue/build/env/bin/hue kt_renewer has restarted more than 3 times in the last 6 seconds
[14/Jun/2021 07:03:23 ] supervisor   WARNING  Supervisor shutting down!
[14/Jun/2021 07:03:23 ] supervisor   WARNING  Waiting for children to exit for 5 seconds...
[2021-06-14 07:03:23 +0000] [19] [INFO] Handling signal: int
[2021-06-14 07:03:23 +0000] [47] [INFO] Worker exiting (pid: 47)
[2021-06-14 07:03:24 +0000] [19] [INFO] Shutting down: Master

Hue version or source? (e.g. open source 4.5, CDH 5.16, CDP 1.0…). System info (e.g. OS, Browser…). open source 4.9, open source 4.10

[mwullink]

please fix in next version, should be easy fix.

[Harshg999]

Added the packages via https://github.com/cloudera/hue/pull/2797.