Hiding labels do not work as expected

**Describe the bug**
When hiding a label, from the dropdown on the top right corner, only the labels are hidden, but not the related issues & PRs.

**To Reproduce**

1. Open any repository with active labels.
2. Click on hiding any label.

**Expected behavior**
It should hide the issues & PRs that have the label. The current behaviour is that only the label becomes hidden, but not the related issues & PRs.

I think it makes more sense that when a user clicks on hiding a label, the user wants to hide the relevant issues & PRs with the label.

**Screenshots**


After hiding the label `difficulty.Easy`:


**Desktop (please complete the following information):**

- OS: Windows 10
- Browser Chrome
- Version 1.1.0

**Additional context**
As discussed in #230

Reproduce the issue from the repository's label-hiding dropdown using the steps in the report, then trace the label filtering entry point in the frontend. Confirm how hidden labels currently affect labels versus issues and pull requests. Done means hiding a label also removes related issues and pull requests from the displayed results, with the existing behavior checked against the report.

Written by the indexing model from the issue text.