Use ArgumentNullException.ThrowIfNull helper method

Did a simple search/replace on the whole repo (except the RSSDP project)
This reduces LOC and should improve performance (methods containing a throw statement don't get inlined)

```
if \((\w+) == null\)
\s+\{
\s+throw new ArgumentNullException\((.*)\);
\s+\}
```

```
ArgumentNullException.ThrowIfNull($1);
```

1 files changed, 1 insertions, 4 deletions

diff --git a/Emby.Server.Implementations/Library/Resolvers/PhotoResolver.cs b/Emby.Server.Implementations/Library/Resolvers/PhotoResolver.cs
index bc2915db6..af4abfb80 100644
--- a/Emby.Server.Implementations/Library/Resolvers/PhotoResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/PhotoResolver.cs
@@ -91,10 +91,7 @@ namespace Emby.Server.Implementations.Library.Resolvers
 
         internal static bool IsImageFile(string path, IImageProcessor imageProcessor)
         {
-            if (path == null)
-            {
-                throw new ArgumentNullException(nameof(path));
-            }
+            ArgumentNullException.ThrowIfNull(path);
 
             var filename = Path.GetFileNameWithoutExtension(path);