Added Dissect Processor Functionality

[vishalboin]

Description

Implemented Dissect processor functionality.

Design overview:

For each pattern in map -

1. Breakdown the pattern into 2 groups:
   • List of fields
   • List of delimiters
2. Assign the properties of prefix and suffix notations.

(Used regex for above 2 steps. These are executed only once to process the dissect pattern, before processing the logs)

3. For an incoming log, check if the dissect_when expression satisfies

For each mapped field's value if present -

4. Split the string with the help of delimiters and assign the the text beween the delimiters to the fields.
5. Perform the operations on the fields, with the help of the suffix and prefix properties.
6. Convert the field types based on the target_types map provided in the config.
7. Populate the output Json with the fields and their assigned values

Issues Resolved

[None]

Check List

• New functionality includes testing.
• New functionality has been documented.
• New functionality has javadoc added
• Commits are signed with a real name per the DCO

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[oeyh]

Closing in favor of #3363