Update Spectral Library Bug

[nbollis]

If the update spectral library option is checked, but no library is present, the search will continue as usual, but throw an exception when trying to update the library.

This exception does not cause the program to crash, but rather hang indefinitely during the 'Writing PSM results' component of the search task.

The results.txt file contained the following error after forcing the software to close.
MetaMorpheus: version 1.0.2
Data files were processed on a computer running Microsoft Windows 10.0.22621 with a 64-bit Intel(R) Xeon(R) Silver 4214R CPU @ 2.40GHz processor with 24 threads and 96GB installed RAM.
.NET version: .NET 6.0.14
e: System.NullReferenceException: Object reference not set to an instance of an object.
at TaskLayer.PostSearchAnalysisTask.UpdateSpectralLibrary() in C:\projects\metamorpheus\MetaMorpheus\TaskLayer\SearchTask\PostSearchAnalysisTask.cs:line 631
at TaskLayer.PostSearchAnalysisTask.Run() in C:\projects\metamorpheus\MetaMorpheus\TaskLayer\SearchTask\PostSearchAnalysisTask.cs:line 92
at TaskLayer.SearchTask.RunSpecific(String OutputFolder, List1 dbFilenameList, List1 currentRawFileList, String taskId, FileSpecificParameters[] fileSettingsList) in C:\projects\metamorpheus\MetaMorpheus\TaskLayer\SearchTask\SearchTask.cs:line 407
at TaskLayer.MetaMorpheusTask.RunTask(String output_folder, List1 currentProteinDbFilenameList, List1 currentRawDataFilepathList, String displayName) in C:\projects\metamorpheus\MetaMorpheus\TaskLayer\MetaMorpheusTask.cs:line 493e.Message: Object reference not set to an instance of an object.e.InnerException: e.Source: TaskLayere.StackTrace: at TaskLayer.PostSearchAnalysisTask.UpdateSpectralLibrary() in C:\projects\metamorpheus\MetaMorpheus\TaskLayer\SearchTask\PostSearchAnalysisTask.cs:line 631
at TaskLayer.PostSearchAnalysisTask.Run() in C:\projects\metamorpheus\MetaMorpheus\TaskLayer\SearchTask\PostSearchAnalysisTask.cs:line 92
at TaskLayer.SearchTask.RunSpecific(String OutputFolder, List1 dbFilenameList, List1 currentRawFileList, String taskId, FileSpecificParameters[] fileSettingsList) in C:\projects\metamorpheus\MetaMorpheus\TaskLayer\SearchTask\SearchTask.cs:line 407
at TaskLayer.MetaMorpheusTask.RunTask(String output_folder, List1 currentProteinDbFilenameList, List1 currentRawDataFilepathList, String displayName) in C:\projects\metamorpheus\MetaMorpheus\TaskLayer\MetaMorpheusTask.cs:line 493e.TargetSite: Void UpdateSpectralLibrary()