ci(renovate): Fix typo in regex manager keys

renovate.json

@@ -25,7 +25,7 @@
   },
   "regexManagers": [
     {
-      "fileMath": ["Earthfile$"],
+      "fileMatch": ["Earthfile$"],
       "matchStrings": [
           "FROM\\s+(?<depName>(?!\\+)[a-z0-9./-]+):?(?<currentValue>[a-z0-9-.]+)?@?(?<currentDigest>sha256:[a-f0-9]+)?"
       ],
@@ -33,7 +33,7 @@
       "versioningTemplate": "docker"
     },
     {
-      "fileMath": ["images/mirror/Earthfile$"],
+      "fileMatch": ["images/mirror/Earthfile$"],
       "matchStrings": [
         "DO \\+MIRROR --image=\"?'?(?<depName>[^:\\s]+?):(?<currentValue>[^\"]*?)\"?'?\\s"
       ],