Refactor APIEnvelopeJob to use primary constructor

Simplifies APIEnvelopeJob by adopting C# primary constructor syntax.
Removes explicit constructors and initializes logger inline,
enabling direct dependency injection and reducing boilerplate.

EnvelopeGenerator.Jobs/Jobs/APIBackendJobs/APIEnvelopeJob.cs

@@ -9,18 +9,9 @@ using Quartz;
 
 namespace EnvelopeGenerator.Jobs.APIBackendJobs;
 
-public class APIEnvelopeJob : IJob
+public class APIEnvelopeJob(ILogger<APIEnvelopeJob>? logger = null) : IJob
 {
-    private readonly ILogger<APIEnvelopeJob> _logger;
-
-    public APIEnvelopeJob() : this(NullLogger<APIEnvelopeJob>.Instance)
-    {
-    }
-
-    public APIEnvelopeJob(ILogger<APIEnvelopeJob> logger)
-    {
-        _logger = logger;
-    }
+    private readonly ILogger<APIEnvelopeJob> _logger = logger ?? NullLogger<APIEnvelopeJob>.Instance;
 
     public async Task Execute(IJobExecutionContext context)
     {