sln-list: Fix char conversions (dotnet#44661)

Author: edvilme

src/Cli/dotnet/commands/dotnet-sln/list/Program.cs

@@ -46,7 +46,7 @@ private async Task ListAllProjectsAsync(string solutionFileFullPath, Cancellatio
             {
                 paths = solution.SolutionFolders
                     // VS-SolutionPersistence does not return a path object, so there might be issues with forward/backward slashes on different platforms
-                    .Select(folder => Path.GetDirectoryName(folder.Path.TrimStart("/")))
+                    .Select(folder => Path.GetDirectoryName(folder.Path.TrimStart('/')))
                     .ToArray();
             }
             else

test/dotnet-sln.Tests/GivenDotnetSlnList.cs

@@ -101,7 +101,7 @@ public void WhenInvalidSolutionIsPassedItPrintsErrorAndUsage(string solutionComm
                 .Execute(solutionCommand, "InvalidSolution.sln", "list");
             cmd.Should().Fail();
             cmd.StdErr.Should().Contain(
-                string.Format(CommonLocalizableStrings.InvalidSolutionFormatString, Path.Combine(projectDirectory, "InvalidSolution.sln"), "").TrimEnd("."));
+                string.Format(CommonLocalizableStrings.InvalidSolutionFormatString, Path.Combine(projectDirectory, "InvalidSolution.sln"), "").TrimEnd('.'));
             cmd.StdOut.Should().BeVisuallyEquivalentToIfNotLocalized("");
         }
 
@@ -121,7 +121,7 @@ public void WhenInvalidSolutionIsFoundListPrintsErrorAndUsage(string solutionCom
                 .Execute(solutionCommand, "list");
             cmd.Should().Fail();
             cmd.StdErr.Should().Contain(
-                string.Format(CommonLocalizableStrings.InvalidSolutionFormatString, solutionFullPath, "").TrimEnd("."));
+                string.Format(CommonLocalizableStrings.InvalidSolutionFormatString, solutionFullPath, "").TrimEnd('.'));
             cmd.StdOut.Should().BeVisuallyEquivalentToIfNotLocalized("");
         }