fix#14119 property generateApis=false not working (#14126)

Author: iWantUss

modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultGenerator.java

@@ -203,7 +203,7 @@ private Boolean getGeneratorPropertyDefaultSwitch(final String key, final Boolea
     void configureGeneratorProperties() {
         // allows generating only models by specifying a CSV of models to generate, or empty for all
         // NOTE: Boolean.TRUE is required below rather than `true` because of JVM boxing constraints and type inference.
-        generateApis = GlobalSettings.getProperty(CodegenConstants.APIS) != null ? Boolean.TRUE : getGeneratorPropertyDefaultSwitch(CodegenConstants.APIS, null);
+        generateApis = GlobalSettings.getProperty(CodegenConstants.APIS) != null ? Boolean.valueOf(GlobalSettings.getProperty(CodegenConstants.APIS)) : getGeneratorPropertyDefaultSwitch(CodegenConstants.APIS, null);
         generateModels = GlobalSettings.getProperty(CodegenConstants.MODELS) != null ? Boolean.TRUE : getGeneratorPropertyDefaultSwitch(CodegenConstants.MODELS, null);
         generateSupportingFiles = GlobalSettings.getProperty(CodegenConstants.SUPPORTING_FILES) != null ? Boolean.TRUE : getGeneratorPropertyDefaultSwitch(CodegenConstants.SUPPORTING_FILES, null);