Fix some typos (mostly found by codespell) (#1514)

Signed-off-by: Stefan Weil <sw@weilnetz.de>

command_test.go

@@ -1414,16 +1414,16 @@ func TestPersistentHooks(t *testing.T) {
 		name string
 		got  string
 	}{
-		// TODO: currently PersistenPreRun* defined in parent does not
-		// run if the matchin child subcommand has PersistenPreRun.
+		// TODO: currently PersistentPreRun* defined in parent does not
+		// run if the matching child subcommand has PersistentPreRun.
 		// If the behavior changes (https://github.com/spf13/cobra/issues/252)
 		// this test must be fixed.
 		{"parentPersPreArgs", parentPersPreArgs},
 		{"parentPreArgs", parentPreArgs},
 		{"parentRunArgs", parentRunArgs},
 		{"parentPostArgs", parentPostArgs},
-		// TODO: currently PersistenPostRun* defined in parent does not
-		// run if the matchin child subcommand has PersistenPostRun.
+		// TODO: currently PersistentPostRun* defined in parent does not
+		// run if the matching child subcommand has PersistentPostRun.
 		// If the behavior changes (https://github.com/spf13/cobra/issues/252)
 		// this test must be fixed.
 		{"parentPersPostArgs", parentPersPostArgs},

powershell_completions.go

@@ -233,7 +233,7 @@ Register-ArgumentCompleter -CommandName '%[1]s' -ScriptBlock {
             Default {
                 # Like MenuComplete but we don't want to add a space here because
                 # the user need to press space anyway to get the completion.
-                # Description will not be shown because thats not possible with TabCompleteNext
+                # Description will not be shown because that's not possible with TabCompleteNext
                 [System.Management.Automation.CompletionResult]::new($($comp.Name | __%[1]s_escapeStringWithSpecialChars), "$($comp.Name)", 'ParameterValue', "$($comp.Description)")
             }
         }