Core,Tests: no error for non-recursive rec funcs

Don't emit warning for functions that are declared with `rec`
keyword but are non-recursive, as this is handled by another
rule - UnneededRecKeyword.

Author: webwarrior-ws

src/FSharpLint.Core/Rules/Conventions/EnsureTailCallDiagnosticsInRecursiveFunctions.fs

@@ -36,7 +36,7 @@ let runner (args: AstNodeRuleParams) =
             else
                 emitWarning func |> Array.singleton
         else
-            UnneededRecKeyword.emitWarning func |> Array.singleton
+            Array.empty
     | _ -> Array.empty
 
 let rule =

src/FSharpLint.Core/Rules/Conventions/UnneededRecKeyword.fs

@@ -33,7 +33,7 @@ let internal functionCallsItself (checkInfo: FSharpCheckFileResults) (func: Recu
         usage.Symbol.DisplayName = funcName 
         && ExpressionUtilities.rangeContainsOtherRange func.Body.Range usage.Range)
 
-let internal emitWarning (func: RecursiveFunctionInfo) =
+let private emitWarning (func: RecursiveFunctionInfo) =
     { Range = func.Range
       Message =
           String.Format(

tests/FSharpLint.Core.Tests/Rules/Conventions/EnsureTailCallDiagnosticsInRecursiveFunctions.fs

@@ -32,16 +32,12 @@ let rec Foo someParam =
         Assert.IsTrue this.NoErrorsExist
 
     [<Test>]
-    member this.``Should error when function is defined with rec keyword but is not recursive``() =
+    member this.``Should not error when function is defined with rec keyword but is not recursive``() =
         this.Parse """
 let rec Foo someParam =
     ()
 
 module Bar =    
     let Foo = 0"""
 
-        Assert.IsTrue 
-            <| this.ErrorWithMessageExistsAt(
-                """The 'Foo' function has a "rec" keyword, but it is not really recursive, consider removing it.""", 
-                2, 
-                8)
+        Assert.IsTrue this.NoErrorsExist