Fix a test

Author: dkhalanskyjb

core/commonKotlin/src/Instant.kt

@@ -282,8 +282,11 @@ internal fun parseIso(isoString: String): Instant {
         ++i
     }
     val year = when {
-        i > yearStart + 9 -> {
-            parseFailure("Expected at most 9 digits for the year number, got ${i - yearStart}")
+        i > yearStart + 10 -> {
+            parseFailure("Expected at most 10 digits for the year number, got ${i - yearStart}")
+        }
+        i == yearStart + 10 && s[yearStart] >= '2' -> {
+            parseFailure("Expected at most 9 digits for the year number or year 1000000000, got ${i - yearStart}")
         }
         i - yearStart < 4 -> {
             parseFailure("The year number must be padded to 4 digits, got ${i - yearStart} digits")

core/commonKotlin/test/InstantIsoStringsTest.kt

@@ -372,7 +372,7 @@ class InstantIsoStringsTest {
             Instant.DISTANT_FUTURE,
             Instant.DISTANT_PAST,
             Instant.fromEpochSeconds(0, 0),
-            Instant.parse("2020-01-02T03:04:05.6789Z"),
+            parseInstant("2020-01-02T03:04:05.6789Z"),
             Instant.MAX,
             Instant.MIN,
         )
@@ -392,7 +392,7 @@ class InstantIsoStringsTest {
                 if (instant == Instant.MAX && offsetSeconds < 0 ||
                     instant == Instant.MIN && offsetSeconds > 0
                 ) continue
-                val newInstant = Instant.parse("${instant.toString().dropLast(1)}$offsetString")
+                val newInstant = parseInstant("${instant.toString().dropLast(1)}$offsetString")
                 assertEquals(newInstant, instant.minus(offsetSeconds.seconds))
             }
         }