为了回答我的问题，我最终在Apache的000-default（站点配置）文件中这样做：

# + --------------------------------------------------------------------------------------------------------------------------- +
# | Prevent access.log spam of the Docker Healthcheck                                                                           |
# | Refs:                                                                                                                       |
# | https://httpd.apache.org/docs/2.2/mod/mod_setenvif.html                                                                     |
# | https://www.linuxquestions.org/questions/linux-server-73/need-to-exclude-certain-messages-from-apache-access_log-4175543280 |
# + --------------------------------------------------------------------------------------------------------------------------- +
<IfModule setenvif_module>
    # If UA matches healthcheck, set 'nolog' env var, which we exclude from the log(s) in the logformat section below.
    BrowserMatchNoCase ^healthcheck nolog
</IfModule>

CustomLog ${APACHE_LOG_DIR}/access.log combined env=!nolog

请注意，我已将自定义运行状况检查UserAgent设置为：HealthCheck: Docker/1.0：

HEALTHCHECK CMD curl -ILfSs http://localhost:80 -A "HealthCheck: Docker/1.0" || exit 1

谢谢你，汉斯，为我指明了正确的方向。