Use type to detect password fields in integrations instead of name

What does this MR do?

When updating integration settings, password fields only need to be filled in if the user wants to change them, otherwise the previous values would be preserved.

This relied on clearing blank params with the name password, but some integrations use a different name, such as api_key in the Datadog integration. So instead we check for fields with type: 'password', which is also what the frontend does to decide how to render these fields in the DynamicField component.

Fixes #328239 (closed)

How to setup and validate locally (strongly suggested)

1. Create a project and go to Settings → Integrations
2. Open the Atlassian Bamboo integration, fill the form with dummy values, and save it (making sure it succeeds).
3. Save the form again, and see that no validation errors are shown.
4. Do the same with the Datadog integration (saving the second time without any changes), and see the validation errors for the API key field.

Does this MR meet the acceptance criteria?

Conformity

• I have included changelog trailers, or none are needed. (Does this MR need a changelog?)
• [-] I have added/updated documentation, or it's not needed. (Is documentation required?)
• [-] I have properly separated EE content from FOSS, or this MR is FOSS only. (Where should EE code go?)
• [-] I have added information for database reviewers in the MR description, or it's not needed. (Does this MR have database related changes?)
• I have self-reviewed this MR per code review guidelines.
• This MR does not harm performance, or I have asked a reviewer to help assess the performance impact. (Merge request performance guidelines)
• I have followed the style guides.
• This change is backwards compatible across updates, or this does not apply.

Availability and Testing

• I have added/updated tests following the Testing Guide, or it's not needed. (Consider all test levels. See the Test Planning Process.)
• [-] I have tested this MR in all supported browsers, or it's not needed.
• [-] I have informed the Infrastructure department of a default or new setting change per definition of done, or it's not needed.

Related to #328239 (closed)