Move issue template labels to config.yml

.github/ISSUE_TEMPLATE/bug_report.md

@@ -1,6 +1,5 @@
 ---
 name: Bug Report
-labels: ["bug :bug:"]
 ---
 
 <!--## Prerequisites

.github/ISSUE_TEMPLATE/config.yml

@@ -1,13 +1,13 @@
 blank_issues_enabled: false
 contact_links:
   - name: Bug Report
-    url: https://github.com/ethereum/solidity/issues/new?template=bug_report.md&projects=ethereum/solidity/43
+    url: https://github.com/ethereum/solidity/issues/new?template=bug_report.md&projects=ethereum/solidity/43&labels=bug+%3Abug%3A
     about: Bug reports about the Solidity Compiler.
   - name: Documentation Issue
-    url: https://github.com/ethereum/solidity/issues/new?template=documentation_issue.md&projects=ethereum/solidity/43
+    url: https://github.com/ethereum/solidity/issues/new?template=documentation_issue.md&projects=ethereum/solidity/43&labels=documentation+%3Abook%3A
     about: Solidity documentation.
   - name: Feature Request
-    url: https://github.com/ethereum/solidity/issues/new?template=feature_request.md&projects=ethereum/solidity/43
+    url: https://github.com/ethereum/solidity/issues/new?template=feature_request.md&projects=ethereum/solidity/43&labels=feature
     about: Solidity language or infrastructure feature requests.
   - name: Report a security vulnerability
     url: https://github.com/ethereum/solidity/security/policy

.github/ISSUE_TEMPLATE/documentation_issue.md

@@ -1,6 +1,5 @@
 ---
 name: Documentation Issue
-labels: ["documentation :book:"]
 ---
 
 ## Page

.github/ISSUE_TEMPLATE/feature_request.md

@@ -1,6 +1,5 @@
 ---
 name: Feature Request
-labels: ["feature"]
 ---
 
 <!--## Prerequisites