test_gc.rb: Attempt to stabilize test_interrupt_in_finalizer

This fails way too often across many environments. I don't think this
test is healthy.
https://github.com/ruby/ruby/actions/runs/17343611722/job/49240735401

Before we give up on it, let me see if this helps.

1 files changed, 1 insertions, 1 deletions

diff --git a/test/ruby/test_gc.rb b/test/ruby/test_gc.rb
index 7aba333e92..d88b4f07f6 100644
--- a/test/ruby/test_gc.rb
+++ b/test/ruby/test_gc.rb
@@ -747,7 +747,7 @@ class TestGc < Test::Unit::TestCase
       Signal.trap(:INT, 'DEFAULT')
       pid = $$
       Thread.start do
-        10.times {
+        1000.times {
           sleep 0.1
           Process.kill("INT", pid) rescue break
         }