improved : updated print-patterns.md file

[sujoy-coder]

Fixes #89

Short description of what this resolves:

pattern printing logic added.

What Changes proposed in this pull request:

• Explanation of Pattern Printing
• Examples with Codes (java)
• Relevant Image added
• File updated : print-patterns.md

Checklist

• Added description of change
• Added file name matches File name guidelines
• Added code examples, test must pass
• Added documentation so that the program is self-explanatory and educational.
• Relevant documentation/comments is changed or added
• PR title follows semantic commit guidelines
• Search previous suggestions before making a new one, as yours may be a duplicate.
• I acknowledge that all my contributions will be made under the project's license.

Notes:

[Utkarsh1504]

@sujoy-coder Nicely done! the explanation is not accurate though but we can improve it later. Thank you for your contribution🎈🎉🎉