Update links.

Author: smillst

checker/src/main/java/org/checkerframework/checker/index/qual/IndexFor.java

@@ -11,7 +11,7 @@
  * different lengths.
  *
  * <p>The <a
- * href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/String.html#charAt-int-">
+ * href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/String.html#charAt(int)">
  * {@code String.charAt(int)}</a> method is declared as
  *
  * <pre>{@code

checker/src/main/java/org/checkerframework/checker/index/qual/IndexOrHigh.java

@@ -8,7 +8,7 @@
  * sequence's length.
  *
  * <p>The <a
- * href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/Arrays.html#binarySearch-java.lang.Object:A-int-int-java.lang.Object-">
+ * href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/Arrays.html#binarySearch(java.lang.Object%5B%5D,int,int,java.lang.Object)">
  * {@code Arrays.binarySearch}</a> method is declared as
  *
  * <pre>{@code

checker/src/main/java/org/checkerframework/checker/index/qual/IndexOrLow.java

@@ -7,7 +7,7 @@
  * An integer that is either -1 or is a valid index for each of the given sequences.
  *
  * <p>The <a
- * href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/String.html#indexOf-java.lang.String-">
+ * href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/String.html#indexOf(java.lang.String)">
  * {@code String.indexOf(String)}</a> method is declared as
  *
  * <pre><code>

docs/tutorial/webpages/user-input-cmd.html

@@ -166,7 +166,7 @@ <h4>3. Run the Regex Checker</h4>
 
         <p>The "incompatible types" warning indicates that variable
         <code>regex</code> is not of type <code>@Regex String</code> which
-        is required for strings passed to <a href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/regex/Pattern.html#compile-java.lang.String-"><code>Pattern.compile()</code></a>.</p>
+        is required for strings passed to <a href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/regex/Pattern.html#compile(java.lang.String)"><code>Pattern.compile()</code></a>.</p>
       </div>
 
       <div id="validate">