S2698: improve issue reporting

S2698 suffers from multiple problems related to issue reporting that we should improve.

• duplicate issues:
  This code will report one issue for each matches.

  assertThat("ABC")
   .matches("A")
   .matches("B")
   .matches("C");
  

• the whole assertion is highlighted

  assertThrows(IllegalArgumentException.class,
        () -> //Huge code...)); // Everything is highlighted!!
  

  Can we do better? Only highlight one method call?

• confusing behavior when the message is misplaced for fest assert (and AssertJ once SONARJAVA-3349 will be done)
  This call
  assertThat("").isEqualTo("").as("Message");
  will highlight
  assertThat("").isEqualTo("")
  claiming that a message is missing, it is not trivial to understand that it is actually misplaced.
  RSPEC-5833 will report that "as()" will not be applied, but this rule could still report that it is misplaced (or simply say to add a message before the assertion). In addition, highlighting should be on the assertion method name. (isEqualTo() in this case)

• FP when a generic assertion is not an assertion predicate:

  org.assertj.core.api.Assertions.assertThat("").usingComparator(null).as("a").isEqualTo(222);