Disable monitoring on Windows (backport #250)

[mergify]

Description

Fixes #248
Disable RTI Monitoring on Windows
Update README.md to describe existing RTI_MONITORING2_ENABLE environment variable

Is this user-facing behavior change?

Yes, monitoring will now be disabled by default on Windows

Did you use Generative AI?

No

Additional Information

---

This is an automatic backport of pull request #250 done by Mergify.

[mergify]

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[fujitatomoya]

Pulls: #252
Gist: https://gist.githubusercontent.com/fujitatomoya/b703740f622e4cd5c08e780ee69a3827/raw/bf13d6831b8b1190a8b606ee0b13a1aac3c95827/ros2.repos
BUILD args: --packages-above-and-dependencies rmw_connextdds_common
TEST args: --packages-above rmw_connextdds_common
ROS Distro: lyrical
Job: ci_launcher
ci_launcher ran: https://ci.ros2.org/job/ci_launcher/20112

• Linux
• Linux-aarch64
• Linux-rhel
• Windows

[fgallegosalido]

@fujitatomoya the Linux build failed at the start

[fujitatomoya]

Pulls: #252
Gist: https://gist.githubusercontent.com/fujitatomoya/2bf48e84f28a7c7341aa1bfce6eb7b1d/raw/bf13d6831b8b1190a8b606ee0b13a1aac3c95827/ros2.repos
BUILD args: --packages-above-and-dependencies rmw_connextdds_common
TEST args: --packages-above rmw_connextdds_common
ROS Distro: lyrical
Job: ci_launcher
ci_launcher ran: https://ci.ros2.org/job/ci_launcher/20158

• Linux
• Linux-aarch64
• Linux-rhel
• Windows

[fgallegosalido]

@fujitatomoya the Linux test seems to not have run correctly. The Windows build failures, apart from two that we already know are flaky, the rest don't seem related to the Connext RMW.

[fujitatomoya]

Pulls: #252
Gist: https://gist.githubusercontent.com/fujitatomoya/9fec13bf915d1589552aff01bf17044a/raw/bf13d6831b8b1190a8b606ee0b13a1aac3c95827/ros2.repos
BUILD args: --packages-above-and-dependencies rmw_connextdds_common
TEST args: --packages-above rmw_connextdds_common
ROS Distro: lyrical
Job: ci_launcher
ci_launcher ran: https://ci.ros2.org/job/ci_launcher/20226

• Linux
• Linux-aarch64
• Linux-rhel
• Windows

[fgallegosalido]

@fujitatomoya Windows and Linux test failures don't seem related to the Connext RMW. I think this is ready to be merged