Fix MethodAccessException when configuring EF Core DB context

[DiFFoZ]

Fixes the exception that throws on non-Mono runtimes

[10:45:49 INF][OpenMod.Runtime.OpenModHostedService] Initializing for host: Openmod Standalone v0.0.0+b482449e2623fe726bac734274e1dcd532c259d3
[10:45:49 INF][OpenMod.Runtime.OpenModHostedService] Loading plugins...
[10:45:49 ERR][OpenMod.Core.Plugins.PluginActivator] Failed to load plugin from type: Shops.ShopsPlugin in assembly: Shops-91f958, Version=2.0.5.0, Culture=neutral, PublicKeyToken=null
System.MethodAccessException: Attempt by method 'OpenMod.EntityFrameworkCore.MySql.Extensions.MySqlContainerBuilderExtensions.AddMySqlDbContextInternal(Autofac.ContainerBuilder, System.Type, System.Action`1<Microsoft.EntityFrameworkCore.DbContextOptionsBuilder>, System.Nullable`1<Microsoft.Extensions.DependencyInjection.ServiceLifetime>)' to access method 'OpenMod.EntityFrameworkCore.Extensions.EntityFrameworkCoreContainerBuilderExtensions.AddDbContextInternal(Autofac.ContainerBuilder, System.Type, System.Action`1<Microsoft.EntityFrameworkCore.DbContextOptionsBuilder>, System.Nullable`1<Microsoft.Extensions.DependencyInjection.ServiceLifetime>, OpenMod.EntityFrameworkCore.Configurator.IDbContextConfigurator)' failed.
   at OpenMod.EntityFrameworkCore.MySql.Extensions.MySqlContainerBuilderExtensions.AddMySqlDbContextInternal(ContainerBuilder containerBuilder, Type dbContextType, Action`1 optionsBuilder, Nullable`1 serviceLifetime)
   at OpenMod.EntityFrameworkCore.MySql.Extensions.MySqlContainerBuilderExtensions.AddMySqlDbContext[T](ContainerBuilder containerBuilder)
   at OpenMod.Core.Plugins.PluginActivator.<>c__DisplayClass11_1.<TryActivatePluginAsync>b__0(ContainerBuilder containerBuilder)
   at Autofac.Core.Lifetime.LifetimeScope.CreateScopeRestrictedRegistry(Object tag, Action`1 configurationAction)
   at Autofac.Core.Lifetime.LifetimeScope.BeginLifetimeScope(Object tag, Action`1 configurationAction)
   at OpenMod.Core.Ioc.LifetimeScopeExtensions.BeginLifetimeScopeEx(ILifetimeScope this, Action`1 configurationAction)
   at OpenMod.Core.Plugins.PluginActivator.<TryActivatePluginAsync>d__11.MoveNext()