Can't play bags with v9 metadata

[roncapat]

When recording a bag after merge of #1476, and you later want to replay it, metadata.yaml parsing fails. Most probably, we do not have in place a test that records and then plays back (?).

See also ros-visualization/rqt_bag#146 since I noticed this by starting to test the rolling branch on a real project and initially thought that the problem was in rqt_bag.

Very simple to reproduce:

• do ros bag record ...
• do ros bag play ...

CC: @MichaelOrlov I will start looking at it ASAP

[roncapat]

Sorry for the noise... I tested rosbag2 rolling in an iron distribution... and apparently something doesn't work as it should be in this mix. Rolling correclty works fine.

[MichaelOrlov]

I tested rosbag2 rolling in an iron distribution... and apparently something doesn't work as it should be in this mix.

Likely because of ABI incompatibility. We don't guarantee ABI compatibility between ROS 2 distros.