Try switching to debian base to fix dll load issue

[Cyberboss]

Bug:

System.TypeInitializationException: The type initializer for 'LibGit2Sharp.Core.NativeMethods' threw an exception. ---> System.DllNotFoundException: Unable to load DLL 'git2-2d2a602': The specified module or one of its dependencies could not be found.
 (Exception from HRESULT: 0x8007007E)
   at LibGit2Sharp.Core.NativeMethods.git_libgit2_init()
   at LibGit2Sharp.Core.NativeMethods.LoadNativeLibrary()
   at LibGit2Sharp.Core.NativeMethods..cctor()
   --- End of inner exception stack trace ---
   at LibGit2Sharp.Core.NativeMethods.git_repository_open(git_repository*& repository, FilePath path)
   at LibGit2Sharp.Core.Proxy.git_repository_open(String path)
   at LibGit2Sharp.Repository..ctor(String path, RepositoryOptions options, RepositoryRequiredParameter requiredParameter)
   at MapDiffBot.Core.LocalRepositoryManager.<>c__DisplayClass3_0.<CreateRepositoryObject>b__0() in /src/MapDiffBot/Core/LocalRepositoryManager.cs:line 47
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at MapDiffBot.Core.LocalRepositoryManager.<CreateRepositoryObject>d__3.MoveNext() in /src/MapDiffBot/Core/LocalRepositoryManager.cs:line 45
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()
   at MapDiffBot.Core.LocalRepositoryManager.<TryLoadRepository>d__4.MoveNext() in /src/MapDiffBot/Core/LocalRepositoryManager.cs:line 122
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()
   at MapDiffBot.Core.LocalRepositoryManager.<GetRepository>d__5.MoveNext() in /src/MapDiffBot/Core/LocalRepositoryManager.cs:line 142
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult()
   at MapDiffBot.Core.PayloadProcessor.<GenerateDiffs>d__13.MoveNext() in /src/MapDiffBot/Core/PayloadProcessor.cs:line 232
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at MapDiffBot.Core.PayloadProcessor.<ScanPullRequest>d__12.MoveNext() in /src/MapDiffBot/Core/PayloadProcessor.cs:line 154

Reference: libgit2/libgit2sharp#1533 (comment)