[config reload]Config Reload Enhancement

[dgsudharsan]

What I did

Code changes for HLD: sonic-net/SONiC#1203
Removed the timer based checks for config reload
Added db_migrator to migrate from "has_timer" to "delayed"
Modified package-manager to migrate from "has_timer" to "delayed"

How I did it

Modified relevant files

How to verify it

Added UT to verify

Previous command output (if the output of a command-line utility has changed)

New command output (if the output of a command-line utility has changed)

[xumia]

@dgsudharsan , looks like the PR has an issue, when updating the sonic-utilities for the sonic-buildimage, the build failed, see PR sonic-net/sonic-buildimage#14619, and the build result: https://dev.azure.com/mssonic/build/_build/results?buildId=251574&view=logs&jobId=e2a1d004-6151-514d-dd3b-ba225f574bd9&j=e2a1d004-6151-514d-dd3b-ba225f574bd9&t=84643f3d-b87b-5e33-4d3a-7ffd9da7d441

2023-04-12T09:35:57.6208803Z + sudo LANG=C DOCKER_HOST= chroot ./fsroot-vs sonic-package-manager install --from-tarball target/docker-macsec.gz -y -v DEBUG --enable
2023-04-12T09:35:57.6209021Z sonic_yang(3):All Keys are not parsed in FEATURE
2023-04-12T09:35:57.6209200Z dict_keys(['dhcp_relay'])
2023-04-12T09:35:57.6209403Z sonic_yang(3):exceptionList:["'delayed'"]
2023-04-12T09:35:57.6209571Z sonic_yang(3):Data Loading Failed:All Keys are not parsed in FEATURE
2023-04-12T09:35:57.6209777Z dict_keys(['dhcp_relay'])
2023-04-12T09:35:57.6209940Z exceptionList:["'delayed'"]
2023-04-12T09:35:57.6210067Z Data Loading Failed
2023-04-12T09:35:57.6210181Z All Keys are not parsed in FEATURE
2023-04-12T09:35:57.6210357Z dict_keys(['dhcp_relay'])
2023-04-12T09:35:57.6210524Z exceptionList:["'delayed'"]
2023-04-12T09:35:57.6210646Z Traceback (most recent call last):
2023-04-12T09:35:57.6210914Z   File "/usr/local/lib/python3.9/dist-packages/sonic_yang_ext.py", line 1113, in loadData
2023-04-12T09:35:57.6211082Z     self._xlateConfigDB(xlateFile=xlateFile)
2023-04-12T09:35:57.6211354Z   File "/usr/local/lib/python3.9/dist-packages/sonic_yang_ext.py", line 731, in _xlateConfigDB
2023-04-12T09:35:57.6211520Z     self._xlateConfigDBtoYang(jIn, yangJ)
2023-04-12T09:35:57.6211864Z   File "/usr/local/lib/python3.9/dist-packages/sonic_yang_ext.py", line 717, in _xlateConfigDBtoYang
2023-04-12T09:35:57.6212116Z     self._xlateContainer(cmap['container'], yangJ[key][subkey], \
2023-04-12T09:35:57.6212398Z   File "/usr/local/lib/python3.9/dist-packages/sonic_yang_ext.py", line 696, in _xlateContainer
2023-04-12T09:35:57.6212591Z     raise(Exception("All Keys are not parsed in {}\n{}\nexceptionList:{}".format(table, \
2023-04-12T09:35:57.6212756Z Exception: All Keys are not parsed in FEATURE
2023-04-12T09:35:57.6212928Z dict_keys(['dhcp_relay'])
2023-04-12T09:35:57.6213106Z exceptionList:["'delayed'"]
2023-04-12T09:35:57.6213163Z 

    self.sy.loadData(self.configdbJsonIn)
  File "/usr/local/lib/python3.9/dist-packages/sonic_yang_ext.py", line 1123, in loadData
    raise SonicYangException("Data Loading Failed\n{}".format(str(e)))
sonic_yang_ext.SonicYangException: Data Loading Failed
All Keys are not parsed in FEATURE
dict_keys(['dhcp_relay'])
exceptionList:["'delayed'"]

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/bin/sonic-package-manager", line 8, in <module>
    sys.exit(cli())
  File "/usr/local/lib/python3.9/dist-packages/click/core.py", line 764, in __call__
    return self.main(*args, **kwargs)
  File "/usr/local/lib/python3.9/dist-packages/click/core.py", line 717, in main
    rv = self.invoke(ctx)
  File "/usr/local/lib/python3.9/dist-packages/click/core.py", line 1134, in invoke
    Command.invoke(self, ctx)
  File "/usr/local/lib/python3.9/dist-packages/click/core.py", line 956, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/usr/local/lib/python3.9/dist-packages/click/core.py", line 555, in invoke
    return callback(*args, **kwargs)
  File "/usr/local/lib/python3.9/dist-packages/click/decorators.py", line 17, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/usr/local/lib/python3.9/dist-packages/sonic_package_manager/main.py", line 149, in cli
    ctx.obj = PackageManager.get_manager()
  File "/usr/local/lib/python3.9/dist-packages/sonic_package_manager/manager.py", line 1006, in get_manager
    cfg_mgmt = config_mgmt.ConfigMgmt(source=INIT_CFG_JSON, sonicYangOptions=ly.LY_CTX_DISABLE_SEARCHDIR_CWD)
  File "/usr/local/lib/python3.9/dist-packages/config/config_mgmt.py", line 66, in __init__
    raise Exception('ConfigMgmt Class creation failed')
Exception: ConfigMgmt Class creation failed

[dgsudharsan]

@xumia This is due to a cyclic dependency with buildimage PR and I have updated sonic-buildimage PR with submodule update of sonic-utilities and sonic-host-services sonic-net/sonic-buildimage#13969. Once the above PR is merged you shouldn't see error