Fix formatting `whats-new.rst` for doc-building #1198

Job	Run time
detect ci trigger	9s
Build (3.8 \| ubuntu-latest)	1m 1s
Build (upstream-dev)	1m 28s
Build (3.9 \| ubuntu-latest)	56s
Build (3.10 \| ubuntu-latest)	55s
Build (3.11 \| ubuntu-latest)	1m 8s
Build (3.12 \| ubuntu-latest)	52s
Build (cloud-data-tests \| ${{ matrix.variable_id }} \| ${{ matrix.experiment_id }} \| ${{ matrix.grid_label }})	0s
	6m 29s

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