Bump actions/stale from 10 to 11 - #135

Change 'List<Rule>' in 'Details.Rule' to use 'Collection<T>', 'ReadOnlyCollection<T>' or 'KeyedCollection<K,V>' (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1002)

Change 'List<Check>' in 'Rule.Check' to use 'Collection<T>', 'ReadOnlyCollection<T>' or 'KeyedCollection<K,V>' (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1002)

Change 'List<Job>' in 'Jobs.AllJobs' to use 'Collection<T>', 'ReadOnlyCollection<T>' or 'KeyedCollection<K,V>' (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1002)

Change 'AllJobs' to be read-only by removing the property setter (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca2227)

Dereference of a possibly null reference.

Possible null reference argument for parameter 'path1' in 'string Path.Combine(string path1, string path2)'.

Possible null reference return.

Converting null literal or possible null value to non-nullable type.

Possible null reference argument for parameter 'path' in 'void Directory.Delete(string path, bool recursive)'.