Define `Error` structure in `common.Message`. #7763

Job	Run time
Build, test and upload wheel	1m 25s
Strategy / FedMedian	1m 10s
Framework / bare	2m 46s
Strategy / FedTrimmedAvg	1m 14s
Framework / bare-https	1m 17s
Strategy / QFedAvg	1m 19s
Framework / jax	1m 57s
Strategy / FaultTolerantFedAvg	1m 19s
Framework / pytorch	2m 45s
Strategy / FedAvgM	1m 14s
Framework / tensorflow	3m 8s
Strategy / FedAdam	1m 18s
Strategy / FedAdagrad	1m 18s
Framework / tabnet	2m 39s
Strategy / FedYogi	1m 11s
Framework / opacus	2m 43s
Framework / pytorch-lightning	2m 37s
Framework / scikit-learn	2m 35s
Framework / fastai	4m 2s
Framework / pandas	1m 51s
	39m 48s

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