In YAML >= 1.2 duiplicated keys, even `>>`
are not allowed [1], and should lead to errors
like `Duplicate merge keys are never allowed`.
While PyYAML still can parse sunch formatting,
ruamel.yaml will fail right away on attempt to
read/write to such file.
Let's remove pre-YAML 1.2 examples from our
documentations to ensure compatability.
[1] https://yaml.org/spec/1.2.2/#3213-node-comparison
Change-Id: I954f46a393df46442dd39798d6e7d8500a5702f0
Signed-off-by: Dmitriy Rabotyagov <dmitriy.rabotyagov@cleura.com>
7237feaa10