remove pl3x references

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -56,7 +56,7 @@ body:
       label: Agreements
       description: Please agree to the following.
       options:
-        - label: I am running the latest version of Purpur available from https://purpur.pl3x.net/downloads.
+        - label: I am running the latest version of Purpur available from https://purpurmc.org/downloads.
           required: true
         - label: I have searched for and ensured there isn't already an open issue regarding this.
           required: true

.github/ISSUE_TEMPLATE/config.yml

@@ -1,8 +1,8 @@
 blank_issues_enabled: false
 contact_links:
   - name: Feature Request
-    url: https://github.com/pl3xgaming/Purpur/discussions/new
+    url: https://github.com/PurpurMC/Purpur/discussions/new
     about: Suggest an idea for Purpur
   - name: Purpur Discord
-    url: https://purpur.pl3x.net/discord
+    url: https://purpurmc.org/discord
     about: If you are having issues with timings or have other minor issues, come join our Discord server for help!

.github/ISSUE_TEMPLATE/performance_problem.yml

@@ -44,7 +44,7 @@ body:
       label: Agreements
       description: Please agree to the following.
       options:
-        - label: I am running the latest version of Purpur available from https://purpur.pl3x.net/downloads.
+        - label: I am running the latest version of Purpur available from https://purpurmc.org/downloads.
           required: true
         - label: I have searched for and ensured there isn't already an open issue regarding this.
           required: true

.github/ISSUE_TEMPLATE/server_crash.yml

@@ -59,7 +59,7 @@ body:
       label: Agreements
       description: Please agree to the following.
       options:
-        - label: I am running the latest version of Purpur available from https://purpur.pl3x.net/downloads.
+        - label: I am running the latest version of Purpur available from https://purpurmc.org/downloads.
           required: true
         - label: I have searched for and ensured there isn't already an open issue regarding this.
           required: true