Fix new ESLint issues

Author: andyleejordan

src/features/PesterTests.ts

@@ -53,9 +53,7 @@ export class PesterTestsFeature implements vscode.Disposable {
         launchType: LaunchType,
         fileUri?: vscode.Uri): Promise<boolean> {
 
-        if (fileUri === undefined) {
-            fileUri = vscode.window.activeTextEditor?.document.uri;
-        }
+        fileUri ??= vscode.window.activeTextEditor?.document.uri;
 
         if (fileUri === undefined) {
             return false;

src/logging.ts

@@ -140,9 +140,9 @@ export class Logger implements ILogger {
 export class LanguageClientOutputChannelAdapter implements LogOutputChannel {
     private _channel: LogOutputChannel | undefined;
     private get channel(): LogOutputChannel {
-        if (!this._channel) {
-            this._channel = window.createOutputChannel(this.channelName, {log: true});
-        }
+        this._channel ??= window.createOutputChannel(this.channelName, {
+            log: true,
+        });
         return this._channel;
     }
 

src/platform.ts

@@ -631,9 +631,7 @@ class PossiblePowerShellExe implements IPossiblePowerShellExe {
         public readonly suppressWarning = false) { }
 
     public async exists(): Promise<boolean> {
-        if (this.knownToExist === undefined) {
-            this.knownToExist = await utils.checkIfFileExists(this.exePath);
-        }
+        this.knownToExist ??= await utils.checkIfFileExists(this.exePath);
         return this.knownToExist ?? false;
     }
 }