Remove redundant @OptIn

libraries/stdlib/src/kotlin/collections/Sequences.kt

@@ -140,7 +140,7 @@ public fun <T> Sequence<T>.shuffled(random: Random): Sequence<T> = sequence<T> {
     val buffer = toMutableList()
     while (buffer.isNotEmpty()) {
         val j = random.nextInt(buffer.size)
-        val last = @OptIn(ExperimentalStdlibApi::class) buffer.removeLast()
+        val last = buffer.removeLast()
         val value = if (j < buffer.size) buffer.set(j, last) else last
         yield(value)
     }

libraries/stdlib/src/kotlin/random/Random.kt

@@ -369,7 +369,6 @@ public fun Random.nextLong(range: LongRange): Long = when {
 internal expect fun defaultPlatformRandom(): Random
 internal expect fun doubleFromParts(hi26: Int, low27: Int): Double
 
-@OptIn(ExperimentalStdlibApi::class)
 internal fun fastLog2(value: Int): Int = 31 - value.countLeadingZeroBits()
 
 /** Takes upper [bitCount] bits (0..32) from this number. */

libraries/stdlib/src/kotlin/text/Strings.kt

@@ -500,7 +500,6 @@ public fun String.substringAfterLast(delimiter: String, missingDelimiterValue: S
  * @param startIndex the index of the first character to be replaced.
  * @param endIndex the index of the first character after the replacement to keep in the string.
  */
-@OptIn(ExperimentalStdlibApi::class)
 public fun CharSequence.replaceRange(startIndex: Int, endIndex: Int, replacement: CharSequence): CharSequence {
     if (endIndex < startIndex)
         throw IndexOutOfBoundsException("End index ($endIndex) is less than start index ($startIndex).")
@@ -546,7 +545,6 @@ public inline fun String.replaceRange(range: IntRange, replacement: CharSequence
  *
  * [endIndex] is not included in the removed part.
  */
-@OptIn(ExperimentalStdlibApi::class)
 public fun CharSequence.removeRange(startIndex: Int, endIndex: Int): CharSequence {
     if (endIndex < startIndex)
         throw IndexOutOfBoundsException("End index ($endIndex) is less than start index ($startIndex).")

libraries/stdlib/src/kotlin/time/Duration.kt

@@ -725,7 +725,6 @@ public value class Duration internal constructor(private val rawValue: Long) : C
      *
      * @sample samples.time.Durations.toIsoString
      */
-    @OptIn(ExperimentalStdlibApi::class)
     public fun toIsoString(): String = buildString {
         if (isNegative()) append('-')
         append("PT")