Fixes XML parsing error for JUnit testing report containing large input node

What does this MR do?

This MR fixes an XML parsing error for our JUnit testing report containing large input node such as this file.

As we can see from this Sentry log the call to Hash.from_xml is failing to parse a large input and returns the following error:

Looks like Nokogiri is raising error when processing large node input as you can see from the source code.

Nokogiri::XML::SyntaxError: 6:10003459: FATAL: internal error: Huge input lookup

Which ends up by returning a 500 error to the end user as you can see here.

Screenshots

Before

After

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team

Closes #25357 (closed)