Add minor documentation corrections and remove unneeded changes

Author: Joseph Sun

src/coverlet.collector/DataCollection/CoverageWrapper.cs

@@ -70,10 +70,5 @@ public void PrepareModules(Coverage coverage)
     {
       coverage.PrepareModules();
     }
-
-    public void UnloadModule(Coverage coverage, string modulePath)
-    {
-      coverage.UnloadModule(modulePath);
-    }
   }
 }

src/coverlet.collector/Utilities/Interfaces/ICoverageWrapper.cs

@@ -39,12 +39,5 @@ internal interface ICoverageWrapper
     /// <param name="coverage"></param>
     void PrepareModules(Coverage coverage);
 
-    /// <summary>
-    /// Unload module in the specified path
-    /// </summary>
-    /// <param name="coverage"></param>
-    /// <param name="modulePath"> path of the module to be unloaded</param>
-    void UnloadModule(Coverage coverage, string modulePath);
-
   }
 }

src/coverlet.core/Coverage.cs

@@ -334,7 +334,7 @@ public CoverageResult GetCoverageResult()
 
     /// <summary>
     /// Invoke the unloading of modules and restoration of the original assembly files, made public to allow unloading
-    /// of instrumentation is testing using parallelization
+    /// of instrumentation in large scale testing utilising parallelization
     /// </summary>
     /// <param name="modulePath"></param>
     public void UnloadModule(string modulePath)