fix: don't delete cfssl and cfssljson (#589)

With #568 these executables are no longer downloaded on demand, but
rather predownloaded to the system.

When running dotnet build locally, it attempts to run `./cfssl` and
`./cfssljson` from `/operator` or `$CFSSL_EXECUTABLES_PATH`. However, it
deletes them after it's done.

Next time you try build again after cleaning the local dir it'll fail.

Co-authored-by: Christoph Bühler <[email protected]>

src/KubeOps/Operator/Commands/CommandHelpers/CertificateGenerator.cs

@@ -49,8 +49,6 @@ public void Dispose()
     {
         Delete(_caconfig);
         Delete(_cacsr);
-        Delete(_cfssl);
-        Delete(_cfssljson);
         Delete(_servercsr);
     }