Add a new database type: GaussDB

[pangpang20]

Describe your changes:

Fixes

I worked on adding a new database type GaussDB because OpenMetadata currently lacks native support for GaussDB, which is essential for our ingestion and metadata management use cases. I tested my changes by running ingestion workflows using a GaussDB instance and validating that metadata was correctly captured.

Type of change:

• New feature

Checklist:

• I have read the CONTRIBUTING document.

• My PR title is Fixes <issue-number>: <short explanation>

• I have commented on my code, particularly in hard-to-understand areas.

• For JSON Schema changes: I updated the migration scripts or explained why it is not needed.

• I have added a test that covers the exact scenario we are fixing. For complex issues, comment the issue number in the test for future reference.

[github-actions]

Hi there 👋 Thanks for your contribution!

The OpenMetadata team will review the PR shortly! Once it has been labeled as safe to test, the CI workflows
will start executing and we'll be able to make sure everything is working as expected.

Let us know if you need any help!

[harshach]

@pangpang20 thanks for the PR.

[github-actions]

The Java checkstyle failed.

Please run mvn spotless:apply in the root of your repository and commit the changes to this PR.
You can also use pre-commit to automate the Java code formatting.

You can install the pre-commit hooks with make install_test precommit_install.

[github-actions]

The Python checkstyle failed.

Please run make py_format and py_format_check in the root of your repository and commit the changes to this PR.
You can also use pre-commit to automate the Python code formatting.

You can install the pre-commit hooks with make install_test precommit_install.

[github-actions]

Jest test Coverage

UI tests summary

Lines	Statements	Branches	Functions
	63.75% (39695/62268)	40.45% (15779/39012)	42.48% (4719/11109)

[sonarqubecloud]

Quality Gate passed for 'open-metadata-ui'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud