Fix a bug with old merge properties being added.

Author: sean-mcmanus

Extension/src/LanguageServer/client.ts

@@ -2186,6 +2186,7 @@ export class DefaultClient implements Client {
             if (configs && configs.length > 0 && configs[0]) {
                 const fileConfiguration: configs.Configuration | undefined = this.configuration.CurrentConfiguration;
                 if (fileConfiguration?.mergeConfigurations) {
+                    configs = deepCopy(configs);
                     configs.forEach(config => {
                         if (fileConfiguration.includePath) {
                             fileConfiguration.includePath.forEach(p => {