FINERACT-2026: Replace HTTPie with curl in Minikube documentation

[Paula-Arias11]

Description

The "Using Minikube" section currently uses http (HTTPie), which is not a standard tool and is missing from the REQUIREMENTS section. This causes a command not found error for most developers. This PR replaces it with curl to ensure consistency with the "How to run for local development" section and to remove undocumented dependencies.

Checklist

Please make sure these boxes are checked before submitting your pull request - thanks!

• Write the commit message as per our guidelines
• Acknowledge that we will not review PRs that are not passing the build ("green") - it is your responsibility to get a proposed PR to pass the build, not primarily the project's maintainers.
• Create/update unit or integration tests for verifying the changes made.
• Follow our coding conventions.
• Add required Swagger annotation and update API documentation at fineract-provider/src/main/resources/static/legacy-docs/apiLive.htm with details of any API changes
• This PR must not be a "code dump". Large changes can be made in a branch, with assistance. Ask for help on the developer mailing list.

Your assigned reviewer(s) will follow our guidelines for code reviews.

[Aman-Mittal]

@Paula-Arias11 Please keep Commit message as same as PR message