Remove toNanosPart for now

Author: cquiroz

core/shared/src/main/scala/org/threeten/bp/Duration.scala

@@ -1215,21 +1215,6 @@ final class Duration private (private val seconds: Long, private val nanos: Int)
     Math.addExact(result, nanos.toLong)
   }
 
-  /**
-   * Get the nanoseconds part within seconds of the duration.
-   *
-   * The length of the duration is stored using two fields - seconds and nanoseconds. The
-   * nanoseconds part is a value from 0 to 999,999,999 that is an adjustment to the length in
-   * seconds. The total duration is defined by calling getNano() and getSeconds().
-   *
-   * This instance is immutable and unaffected by this method call.
-   *
-   * @return
-   *   the nanoseconds within the second part of the length of the duration, from 0 to 999,999,999
-   * @since 9
-   */
-  def toNanosPart: Int = (nanos / Duration.NANOS_PER_SECOND).toInt
-
   /**
    * Compares this duration to the specified {@code Duration}.
    *

tests/shared/src/test/scala/org/threeten/bp/TestDuration.scala

@@ -1938,13 +1938,11 @@ class TestDuration extends AnyFunSuite with AssertionsHelper {
   test("test_toNanos") {
     val test: Duration = Duration.ofSeconds(321, 123456789)
     assertEquals(test.toNanos, 321123456789L)
-    assertEquals(test.toNanosPart, 0L)
   }
 
   test("test_toNanos_max") {
     val test: Duration = Duration.ofSeconds(0, Long.MaxValue)
     assertEquals(test.toNanos, Long.MaxValue)
-    assertEquals(test.toNanosPart, 0L)
   }
 
   test("test_toNanos_tooBig") {