Fix typos

Author: andrykonchin

src/main/java/org/truffleruby/parser/lexer/StringTerm.java

@@ -60,7 +60,7 @@
 
 public class StringTerm extends StrTerm {
 
-    // Chanacters that can be escaped in a %r style regexp literal when they are also the terminator.
+    // Characters that can be escaped in a %r style regexp literal when they are also the terminator.
     private static final Set<Character> REGEXP_ESCAPABLE_TERMINATORS = new HashSet<>(
             Arrays.asList(new Character[]{ '!', '"', '#', '%', '&', '\'', ',', '-', ':', ';', '@', '_', '`' }));
 

src/main/java/org/truffleruby/parser/parser/ParserSupport.java

@@ -645,7 +645,7 @@ private void handleUselessWarn(ParseNode node, String useless) {
                 "Useless use of " + useless + " in void context.");
     }
 
-    /** Check to see if current node is an useless statement. If useless a warning if printed.
+    /** Check to see if current node is a useless statement. If useless a warning if printed.
      *
      * @param node to be checked. */
     public void checkUselessStatement(ParseNode node) {
@@ -1802,7 +1802,7 @@ public RopeWithEncoding setRegexpEncoding(RegexpParseNode end, Rope value) {
 
     protected ClassicRegexp checkRegexpSyntax(Rope value, RegexpOptions options) {
         try {
-            // This is only for syntax checking but this will as a side-effect create an entry in the regexp cache.
+            // This is only for syntax checking but this will as a side effect create an entry in the regexp cache.
             return new ClassicRegexp(
                     getConfiguration().getContext(),
                     value,