Create role based default configs for tedge operation plugins

[albinsuresh]

Is your feature improvement request related to a problem? Please describe.

The tedge-log-plugin and tedge-config-plugin currently creates their configuration files with zero file entries (all example entries commented), as they can run both on main device as well as child devices and those examples only make sense on the main device. Leaving them empty on child devices is acceptable as we can't assume any paths on those devices. But, at least on the main device, some sensible default entries should be present, so that someone using these plugins get to try out those features immediately, without having to update those files.

Describe the solution you'd like

• The default plugin config file contents should be generated based on the role (main device or not)
• The config paths of tedge config files (tedge.toml, system.toml etc) in tedge-configuration-plugin.toml should not assume the default config dir: /etc/tedge but rather derive it from the --config-dir option that's used to invoke that plugin
• The tedge-log-plugin.toml on the main device should at least have the tedge-agent/software-management entries in it.

Describe alternatives you've considered

Additional context

[reubenmiller]

The following would be the suggested default settings both the configuration and log management features:

file: /etc/tedge/plugins/tedge-log-plugin.toml

[[files]]
type = "software-management"
path = "/var/log/tedge/agent/software-*"

file: /etc/tedge/plugins/tedge-configuration-plugin.toml

[[files]]
path = "/etc/tedge/tedge.toml"
type = "tedge.toml"

[[files]]
path = "/etc/tedge/plugins/tedge-log-plugin.toml"
type = "tedge-log-plugin"
user = "tedge"
group = "tedge"
mode = 0o0444

[albinsuresh]

Test

Plugin config defaults updated as the described in the previous comment, where the config and log directory path prefixes used in those default path entries are derived from the values passed in the --config-dir argument and the tedge logs.path configuration respectively.

Tests already exist for the config entries using the default config and log paths:

• configuration_operation.robot::Default plugin configuration
• log_operation::Default plugin configuration.

[gligorisaev]

QA has thoroughly checked the feature and here are the results:

• [x] Test for ticket exists in the test suite.
• tests/RobotFramework/tests/cumulocity/configuration/configuration_operation.robot
• tests/RobotFramework/tests/cumulocity/log/log_operation.robot
• [x] QA has tested the function and it's functioning according description.