[infra] enabling leak detector by default

Fixes #9
Issues like #224 should fail the build now.

infra/base-images/base-runner/Dockerfile

@@ -23,7 +23,7 @@ COPY llvm-symbolizer test_all test_report run_fuzzer /usr/local/bin/
 # Note that these match the settings used in ClusterFuzz and
 # shouldn't be changed unless a corresponding change is made on
 # ClusterFuzz side as well.
-ENV ASAN_OPTIONS="alloc_dealloc_mismatch=0:allocator_may_return_null=1:allocator_release_to_os=1:check_malloc_usable_size=0:detect_container_overflow=1:detect_odr_violation=0:detect_leaks=0:detect_stack_use_after_return=1:fast_unwind_on_fatal=0:handle_abort=1:handle_segv=1:handle_sigill=1:max_uar_stack_size_log=16:print_scariness=1:quarantine_size_mb=10:strict_memcmp=1:strict_string_check=1:strip_path_prefix=/workspace/:symbolize=1:use_sigaltstack=1"
+ENV ASAN_OPTIONS="alloc_dealloc_mismatch=0:allocator_may_return_null=1:allocator_release_to_os=1:check_malloc_usable_size=0:detect_container_overflow=1:detect_odr_violation=0:detect_leaks=1:detect_stack_use_after_return=1:fast_unwind_on_fatal=0:handle_abort=1:handle_segv=1:handle_sigill=1:max_uar_stack_size_log=16:print_scariness=1:quarantine_size_mb=10:strict_memcmp=1:strict_string_check=1:strip_path_prefix=/workspace/:symbolize=1:use_sigaltstack=1"
 ENV MSAN_OPTIONS="print_stats=1:strip_path_prefix=/workspace/:symbolize=1"
 ENV UBSAN_OPTIONS="halt_on_error=1:print_stacktrace=1:print_summary=1:strip_path_prefix=/workspace/:symbolize=1"