2.4.0rc8: Fixes and improvements

What's Changed

• [2.4] Fix Auto login "communication error" by @chesterxgchen in #2280
• [2.4] updates examples, add version matching note by @SYangster in #2281
• [2.4] Fixed the client_executor improper lock use. by @yhwen in #2288
• [2.4] vdr issues [skip ci] by @chesterxgchen in #2286
• [2.4] Add notebook to GNN examples by @ZiyueXu77 in #2290
• [2.4] Fix FLModelUtil by @YuanTingHsieh in #2292
• [2.4] Nemo examples fix by @holgerroth in #2293
• [2.4] Check invalid input directory in nvflare config by @chesterxgchen in #2294
• [2.4] Fix nemo peft notebook by @holgerroth in #2296
• [2.4] Update nemo instructions by @holgerroth in #2298
• [2.4] Update documentation and docstrings by @YuanTingHsieh in #2300
• [2.4] Update execution api type documentation by @YuanTingHsieh in #2304
• [2.4] address vdr feedback by @SYangster in #2299
• [2.4] Added debug headers for all message route in CoreCell for 2.4 Branch by @nvidianz in #2302
• [2.4] Rename to execution api type, update job command output by @SYangster in #2307

Full Changelog: 2.4.0rc7...2.4.0rc8