Bump cache version

ext/bootsnap/bootsnap.c

@@ -82,7 +82,7 @@ struct bs_cache_key {
 STATIC_ASSERT(sizeof(struct bs_cache_key) == KEY_SIZE);
 
 /* Effectively a schema version. Bumping invalidates all previous caches */
-static const uint32_t current_version = 5;
+static const uint32_t current_version = 6;
 
 /* hash of e.g. "x86_64-darwin17", invalidating when ruby is recompiled on a
  * new OS ABI, etc. */

test/compile_cache_key_format_test.rb

@@ -27,7 +27,7 @@ class CompileCacheKeyFormatTest < Minitest::Test
 
   def test_key_version
     key = cache_key_for_file(FILE)
-    exp = [5].pack("L")
+    exp = [6].pack("L")
     assert_equal(exp, key[R[:version]])
   end