Bump xunit from 2.4.1 to 2.7.1 in /src (#3242)

* Bump xunit from 2.4.1 to 2.7.1 in /src

Bumps [xunit](https://github.com/xunit/xunit) from 2.4.1 to 2.7.1.
- [Commits](https://github.com/xunit/xunit/compare/2.4.1...2.7.1)

---
updated-dependencies:
- dependency-name: xunit
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

* Appease xunit warnings after upgrading to v2.7.1

* Appease the whitespace linter

* Appease the whitespace linter

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Patrick Ellis <319655+pje@users.noreply.github.com>

src/Test/L0/CommandLineParserL0.cs

@@ -68,7 +68,7 @@ namespace GitHub.Runner.Common.Tests
                 trace.Info("Parsed");
 
                 trace.Info("Commands: {0}", clp.Commands.Count);
-                Assert.True(clp.Commands.Count == 2);
+                Assert.Equal(2, clp.Commands.Count);
             }
         }
 
@@ -88,7 +88,7 @@ namespace GitHub.Runner.Common.Tests
                 trace.Info("Parsed");
 
                 trace.Info("Args: {0}", clp.Args.Count);
-                Assert.True(clp.Args.Count == 2);
+                Assert.Equal(2, clp.Args.Count);
                 Assert.True(clp.Args.ContainsKey("arg1"));
                 Assert.Equal("arg1val", clp.Args["arg1"]);
                 Assert.True(clp.Args.ContainsKey("arg2"));
@@ -112,7 +112,7 @@ namespace GitHub.Runner.Common.Tests
                 trace.Info("Parsed");
 
                 trace.Info("Args: {0}", clp.Flags.Count);
-                Assert.True(clp.Flags.Count == 2);
+                Assert.Equal(2, clp.Flags.Count);
                 Assert.Contains("flag1", clp.Flags);
                 Assert.Contains("flag2", clp.Flags);
             }