Raise open file limit in jdk build images

[Copilot]

Chrome crashes during CI browser tests because the containers inherit a low nofile limit. This raises the open file limit to 1048576 across all jdk build images (jdk8, jdk11, jdk17, jdk21, jdk25).

Changes

• Dockerfiles: drop a /etc/security/limits.d/99-nofile.conf with soft/hard nofile of 1048576 for all users and root, and enable pam_limits.so in common-session so login/su sessions actually apply it.

RUN mkdir -p /etc/security/limits.d && \
    printf '* soft nofile 1048576\n* hard nofile 1048576\nroot soft nofile 1048576\nroot hard nofile 1048576\n' > /etc/security/limits.d/99-nofile.conf && \
    echo 'session required pam_limits.so' >> /etc/pam.d/common-session

• docker-compose.yaml: add matching ulimits, since the container's limit is ultimately set by the daemon at start time — the in-image PAM config alone does not cover the main container process.

    ulimits:
      nofile:
        soft: 1048576
        hard: 1048576

Note that consumers running these images outside of the provided compose files will still need to pass --ulimit nofile=... themselves.