Only emit one message with accumulated property names

lib/init-action.js

@@ -104438,6 +104438,7 @@ async function loadPropertiesFromApi(logger, repositoryNwo) {
       `Retrieved ${remoteProperties.length} repository properties: ${remoteProperties.map((p) => p.property_name).join(", ")}`
     );
     const properties = {};
+    const unrecognisedProperties = [];
     for (const property of remoteProperties) {
       if (property.property_name === void 0) {
         throw new Error(
@@ -104447,9 +104448,7 @@ async function loadPropertiesFromApi(logger, repositoryNwo) {
       if (isKnownPropertyName(property.property_name)) {
         setProperty2(properties, property.property_name, property.value, logger);
       } else if (property.property_name.startsWith(GITHUB_CODEQL_PROPERTY_PREFIX) && !isDynamicWorkflow()) {
-        logger.warning(
+        unrecognisedProperties.push(property.property_name);
-          `Found a repository property named '${property.property_name}', which looks like a CodeQL Action repository property, but which is not understood by this version of the CodeQL Action. Do you need to update to a newer version?`
-        );
       }
     }
     if (Object.keys(properties).length === 0) {
@@ -104464,6 +104463,12 @@ async function loadPropertiesFromApi(logger, repositoryNwo) {
         logger.debug(`  ${property}: ${value}`);
       }
     }
+    if (unrecognisedProperties.length > 0) {
+      const unrecognisedPropertyList = unrecognisedProperties.map((name) => `'${name}'`).join(", ");
+      logger.warning(
+        `Found repository properties (${unrecognisedPropertyList}), which look like CodeQL Action repository properties, but which are not understood by this version of the CodeQL Action. Do you need to update to a newer version?`
+      );
+    }
     return properties;
   } catch (e) {
     throw new Error(

src/feature-flags/properties.test.ts

@@ -227,7 +227,7 @@ test.serial(
       warningSpy.firstCall.args[0]
         .toString()
         .startsWith(
-          `Found a repository property named '${propertyName}', which looks like a CodeQL Action repository property`,
+          `Found repository properties ('${propertyName}'), which look like CodeQL Action repository properties`,
         ),
     );
   },

src/feature-flags/properties.ts

@@ -118,6 +118,8 @@ export async function loadPropertiesFromApi(
     );
 
     const properties: RepositoryProperties = {};
+    const unrecognisedProperties: string[] = [];
+
     for (const property of remoteProperties) {
       if (property.property_name === undefined) {
         throw new Error(
@@ -131,12 +133,7 @@ export async function loadPropertiesFromApi(
         property.property_name.startsWith(GITHUB_CODEQL_PROPERTY_PREFIX) &&
         !isDynamicWorkflow()
       ) {
-        logger.warning(
+        unrecognisedProperties.push(property.property_name);
-          `Found a repository property named '${property.property_name}', ` +
-            "which looks like a CodeQL Action repository property, " +
-            "but which is not understood by this version of the CodeQL Action. " +
-            "Do you need to update to a newer version?",
-        );
       }
     }
 
@@ -153,6 +150,20 @@ export async function loadPropertiesFromApi(
       }
     }
 
+    // Emit a warning if we encountered unrecognised properties that have our prefix.
+    if (unrecognisedProperties.length > 0) {
+      const unrecognisedPropertyList = unrecognisedProperties
+        .map((name) => `'${name}'`)
+        .join(", ");
+
+      logger.warning(
+        `Found repository properties (${unrecognisedPropertyList}), ` +
+          "which look like CodeQL Action repository properties, " +
+          "but which are not understood by this version of the CodeQL Action. " +
+          "Do you need to update to a newer version?",
+      );
+    }
+
     return properties;
   } catch (e) {
     throw new Error(