.gitignore: reformatted, added patterns for IDEs, for deb packages and for test results

[pasabanov]

Please sign (check) the below before submitting the Pull Request:

• I have signed the ntop Contributor License Agreement at https://github.com/ntop/legal/blob/main/individual-contributor-licence-agreement.md
• I have read the contributing guide lines at https://github.com/ntop/nDPI/blob/dev/CONTRIBUTING.md
• I have updated the documentation (in doc/) to reflect the changes made (if applicable)

Describe changes:

1. Removed unnecessary brackets: *.[o] => *.o.
2. Deleted duplicate line: *o.cmd.
3. Added folders for JetBrains and VS Code IDEs: /.idea/, /.vscode/.
4. Added patterns to ignore file generated by packages/ubuntu/configure and packages/ubuntu/Makefile:

   *.status
   *.substvars
   /packages/...
   

5. Added patterns to ignore test results: *.trs.

I verified that the patterns *.status, *.substvars, and *.trs do not match any extra files, only those that are generated automatically.

[0xA50C1A1]

4. Added patterns to ignore file generated by packages/ubuntu/configure and packages/ubuntu/Makefile:

Special thanks for that.

[IvanNardi]

Thank you!