Update URLs.

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -19,7 +19,7 @@ body:
         - Never be shy to give us screenshots and/or code samples. It will help!
 
         There is a chance that the bug is already fixed in the latest version, but not released yet. 
-        So please check in [Live Editor - Beta](https://beta.mermaid.live) before raising an issue.
+        So please check in [Live Editor - Develop](https://develop.git.mermaid.live) before raising an issue.
   - type: textarea
     attributes:
       label: Description
@@ -46,7 +46,7 @@ body:
     attributes:
       label: Code Sample
       description: |-
-        If applicable, add the code sample or a link to the [Live Editor - Beta](https://beta.mermaid.live).
+        If applicable, add the code sample or a link to the [Live Editor - Develop](https://develop.git.mermaid.live).
         Any text pasted here will be rendered as a Code block.
       render: text
   - type: textarea

.github/ISSUE_TEMPLATE/config.yml

@@ -12,6 +12,9 @@ contact_links:
   - name: Live Editor
     url: https://mermaid.live
     about: Try the live editor to preview graphs in no time.
-  - name: Live Editor - Beta
-    url: https://beta.mermaid.live
+  - name: Live Editor - Develop
+    url: https://develop.git.mermaid.live
     about: Try unreleased changes in the develop branch.
+  - name: Live Editor - Next
+    url: https://next.git.mermaid.live
+    about: Try unreleased changes in the next branch.