Backport "Increase BootstrappedOnlyCompilationTests timeout" to LTS (#20976)

Backports #19868 to the LTS branch.

PR submitted by the release tooling.
[skip ci]

Author: WojciechMazur

compiler/test/dotty/tools/dotc/BootstrappedOnlyCompilationTests.scala

@@ -206,7 +206,7 @@ class BootstrappedOnlyCompilationTests {
 object BootstrappedOnlyCompilationTests extends ParallelTesting {
   // Test suite configuration --------------------------------------------------
 
-  def maxDuration = 60.seconds
+  def maxDuration = 100.seconds
   def numberOfSlaves = Runtime.getRuntime().availableProcessors()
   def safeMode = Properties.testsSafeMode
   def isInteractive = SummaryReport.isInteractive