Fix spelling of Perl 6 (#3672)

Resolves #3671.

samples/Perl 6/grammar-test.p6

@@ -0,0 +1,22 @@
+token pod_formatting_code {
+    $<code>=<[A..Z]>
+    '<' { $*POD_IN_FORMATTINGCODE := 1 }
+    $<content>=[ <!before '>'> <pod_string_character> ]+
+    '>' { $*POD_IN_FORMATTINGCODE := 0 }
+}
+
+token pod_string {
+    <pod_string_character>+
+}
+
+token something:sym«<» {
+    <!>
+}
+
+token name {
+    <!>
+}
+
+token comment:sym<#> {
+   '#' {} \N*
+}