No, this is not a mistake. From Wikipedia article "Football pitch":
Due to the original formulation of the Laws in England and the early supremacy of the four British football associations within IFAB, the standard dimensions of a football pitch were originally expressed in imperial units. The Laws now express dimensions with approximate metric equivalents (followed by traditional units in brackets), but use of the imperial units remains common in some countries, especially in the United Kingdom.
So, 1 yard = 0.9144 meter ≈ 1 meter
From IFAB 1974 minutes of the annual general meeting:
I am not exactly sure when board approved this table of measurement as some meeting files are not available online.