Labels corrected in Issue templates

Author: alisevych

.github/ISSUE_TEMPLATE/bug_report.md

@@ -2,7 +2,7 @@
 name: Bug report
 about: Create a report to help us improve
 title: ''
-labels: 'bug'
+labels: 'cat-bug'
 assignees: ''
 
 ---

.github/ISSUE_TEMPLATE/feature_request.md

@@ -2,7 +2,7 @@
 name: Feature request
 about: Suggest an idea for the UTBot project
 title: ''
-labels: 'enhancement'
+labels: 'cat-enhancement'
 assignees: ''
 
 ---

.github/ISSUE_TEMPLATE/test_request.md

@@ -2,7 +2,7 @@
 name: Manual testing checklist
 about: Checklist of testing process
 title: 'Manual testing of build#'
-labels: 'qa'
+labels: 'cat-qa'
 assignees: ''
 
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