Fix nock url for delete preferences

Description

Issue is with the test suite. This is not a regression and does not effect end user.

The test were printing an error message because the url for nock when deleting a preference was incorrect and the http request didn't succeed.

Expected: No error logs
Observed: Has an error log when running tests

Note: Making a ticket to track a community contribution

QA Test Steps

None

Status

Mana

None

Assignee

Mattermost Community

QA Assignee

None

Reporter

Sudheer Timmaraju

Epic Link

None

Fix versions

Mattermost Team

Apps

Sprint

None

Labels

None

QA Testing Areas

Other (write in QA test steps)

GitHub Issue

None
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