pppoe: T6930: Remove unnecessary code

[natali-rs1985]

Change Summary

In case of changes in config that require reconnect PPPoEIF.remove() function is called and old default routes are removed. So we do not need to do it once again.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Migration from an old Vyatta component to vyos-1x, please link to related PR inside obsoleted component
• Other (please describe):

Related Task(s)

• https://vyos.dev/T6930

Related PR(s)

Component(s) name

interfaces pppoe

Proposed changes

How to test

Smoketest result

vyos@vyos:~$ python3 /usr/libexec/vyos/tests/smoke/cli/test_interfaces_pppoe.py
test_pppoe_authentication (__main__.PPPoEInterfaceTest.test_pppoe_authentication) ... ok
test_pppoe_client (__main__.PPPoEInterfaceTest.test_pppoe_client) ... ok
test_pppoe_client_disabled_interface (__main__.PPPoEInterfaceTest.test_pppoe_client_disabled_interface) ... ok
test_pppoe_dhcpv6pd (__main__.PPPoEInterfaceTest.test_pppoe_dhcpv6pd) ... ok
test_pppoe_mtu_mru (__main__.PPPoEInterfaceTest.test_pppoe_mtu_mru) ... ok
test_pppoe_options (__main__.PPPoEInterfaceTest.test_pppoe_options) ... ok

----------------------------------------------------------------------
Ran 6 tests in 42.767s

OK

Checklist:

• I have read the CONTRIBUTING document
• I have linked this PR to one or more Phabricator Task(s)
• I have run the components SMOKETESTS if applicable
• My commit headlines contain a valid Task id
• My change requires a change to the documentation
• I have updated the documentation accordingly

[github-actions]

👍
No issues in PR Title / Commit Title

[github-actions]

CI integration ❌ failed!

Details

CI logs

• CLI Smoketests (no interfaces) ❌ failed
• CLI Smoketests (interfaces only) ❌ failed
• Config tests 👍 passed
• RAID1 tests 👍 passed
• TPM tests 👍 passed