Fix legacy version lists with 9.0+ entries

Author: cotti

config/legacy-url-mappings.yml

@@ -4,7 +4,7 @@
 # Upon creation of version selection dropdowns, this data is combined with the current version of its product.
 #############################################
 
-stack: &stack [ '9.0+', '8.19', '8.18', '8.17', '8.16', '8.15', '8.14', '8.13', '8.12', '8.11', '8.10', '8.9', '8.8', '8.7', '8.6', '8.5', '8.4', '8.3', '8.2', '8.1', '8.0', '7.17' ]
+stack: &stack [ '8.19', '8.18', '8.17', '8.16', '8.15', '8.14', '8.13', '8.12', '8.11', '8.10', '8.9', '8.8', '8.7', '8.6', '8.5', '8.4', '8.3', '8.2', '8.1', '8.0', '7.17' ]
 
 mappings:
   en/apm/agent/android/:
@@ -129,7 +129,7 @@ mappings:
     legacy_versions: []
   en/ecs/:
     product: ecs
-    legacy_versions: [ '9.0+', '8.18', '8.17', '8.16', '8.15', '8.14', '8.13', '8.12', '8.11', '8.10', '8.9', '8.8', '8.7', '8.6', '8.5', '8.4', '8.3', '8.2', '8.1', '8.0', '1.12', '1.11', '1.10', '1.9', '1.8', '1.7', '1.6', '1.5', '1.4', '1.3', '1.2', '1.1', '1.0' ]
+    legacy_versions: [ '8.18', '8.17', '8.16', '8.15', '8.14', '8.13', '8.12', '8.11', '8.10', '8.9', '8.8', '8.7', '8.6', '8.5', '8.4', '8.3', '8.2', '8.1', '8.0', '1.12', '1.11', '1.10', '1.9', '1.8', '1.7', '1.6', '1.5', '1.4', '1.3', '1.2', '1.1', '1.0' ]
   en/elastic-stack-glossary/:
     product: elastic-stack
     legacy_versions: []