incorrect subtable name used for the relative offset description

[Pomax]

Description

https://learn.microsoft.com/en-us/typography/opentype/spec/gsub#ES has the text: [...] relative to the start of the ExtensionSubstFormat1 subtable., twice, but this should read relative to the start of the SubstExtensionFormat1 subtable, as that's the name given as table heading:

Page URL

https://learn.microsoft.com/en-us/typography/opentype/spec/gsub#lookuptype-7-extension-substitution

Content source URL

https://github.com/MicrosoftDocs/typography/blob/live/typographydocs/opentype/spec/gsub.md