GPU support for bpftime

What's Changed

• feat: Enhance file descriptor management and environment variable par… by @yunwei37 in #438
• fix a race condition and improve performance in userspace ringbuf reservation by @Officeyutong in #430
• fix: cleanup when reattach by @Officeyutong in #439
• GPU: support per-thread GPU ringbuffer by @Officeyutong in #425
• fix: Mocked epoll_wait doesn't support timeout = -1 by @Officeyutong in #442
• [FEATURE] Implement pure data structure maps for queue_map & stack_map by @Sy0307 in #401
• [WIP] Fix new maps example test in new bpftool & libbpf version by @Sy0307 in #445
• [+] New CI for testing bpftime under gcc-13 by @Sy0307 in #446
• Reorder examples and add documents by @yunwei37 in #451
• fix: Resolve compilation failure when BPFTIME_ENABLE_CUDA_ATTACH=1 by @axhmfhnp in #452
• enhances the CUDA benchmarking and add memtrace by @yunwei37 in #453

New Contributors

• @axhmfhnp made their first contribution in #452

Full Changelog: v0.1.0...v0.2.0