Add section to devconfig

[ddutt]

Description

Added support for searching for section or line by regex in device config

Type of change

• New feature (non-breaking change which adds functionality)

New Behavior

Users can now search device config's by section or a specific line to see if it exists in the running config of a device. ...

Contrast to Current Behavior

Users cannot search inside device config with existing code.

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Discussion: Benefits and Drawbacks

Users have often requested the ability to search insde configs for specific lines or sections. This commit enables that now.

Changes to the Documentation

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Proposed Release Note Entry

Added support for searching for a line or section within a device config via the section keyword. The specification can be a simple string or regex.

Double Check

• [x] I have read the comments and followed the CONTRIBUTING.md.
• [x] I have explained my PR according to the information in the comments or in a linked issue.
• [x] My PR source branch is created from the develop branch.
• [x] My PR targets the develop branch.
• [x] All my commits have --signoff applied