test: code format and lint

[luohoufu]

What does this PR do

code format and lint

Rationale for this change

This pull request includes several minor changes across multiple files to improve code readability and maintainability. The changes primarily involve adding blank lines for better separation of code blocks and removing unnecessary blank lines.

Code readability improvements:

• config/config.go: Added a blank line for better separation of the package declaration.
• lib/process/discover.go: Added a blank line after the searchEngineRegx variable declaration for better readability.
• lib/reader/commom/dtfmt/doc.go: Removed unnecessary blank lines to clean up the documentation comments. [1] [2]
• lib/reader/commom/dtfmt/util.go: Added blank lines in the examples to improve readability. [1] [2]

Code cleanup:

• lib/reader/readjson/json.go: Removed an unnecessary blank line in the import section.
• plugin/api/model.go: Removed an unnecessary blank line at the end of the ReadElasticLogFileReq struct.

Standards checklist

• The PR title is descriptive
• The commit messages are semantic
• Necessary tests are added
• Updated the release notes
• Necessary documents have been added if this is a new feature
• Performance tests checked, no obvious performance degradation

[medcl]

config/generated.go should restored rather deleted.