fix: Remove GC before test case execution, because it's slow

Author: kgilpin

lib/appmap/minitest.rb

@@ -142,7 +142,6 @@ class ::Minitest::Test
     alias run_without_hook run
 
     def run
-      GC.start
       AppMap::Minitest.begin_test self, name
       begin
         run_without_hook

lib/appmap/rspec.rb

@@ -87,7 +87,6 @@ def initialize(example)
         end
 
         warn "Starting recording of example #{example}@#{source_location}" if AppMap::RSpec::LOG
-        GC.start
         @trace = AppMap.tracing.trace
         @webdriver_port = webdriver_port.()
       end