Fix single-letter form of wednesday in Spanish

[mindouro]

The single-letter form of Wednesday in Spanish is 'X' and not 'M'.

Quoting Wikipedia: "The Spanish language also has an established convention for days of the week using one letter. These are: L – lunes (Monday); M – martes (Tuesday); X – miércoles (Wednesday); J – jueves (Thursday); V – viernes (Friday), S – sábado (Saturday); and D – domingo (Sunday). Each day of the week is written using its first letter except Wednesday, which is represented by the letter X in order to avoid confusion between martes (Tuesday) and miércoles (Wednesday), which both begin with an m."

[harogaston]

Hi @mindouro thank you for your contribution. I see your point and I agree with your evidence. Nonetheless I have one concern. That use ('x' instead of 'm') makes sense in environments where all days of the week are listed. I am concerned that it makes less sense in isolation - i.e. `x 13 Octubre' looks a bit off.

I would like to have the opinion of other members on this @date-fns/i18n-es

[harshsingh32]

lgtm

[harogaston]

@mindouro You will have to update your PR, there are more files that need changes on order for this to work. Please have a look at the rest of the files i.e.

date-fns/src/locale/es/_lib/match/index.ts

Lines 67 to 76 in 4e56219

	const matchDayPatterns = {
	narrow: /^[dlmjvs]/i,
	short: /^(do|lu|ma|mi|ju|vi|s[áa])/i,
	abbreviated: /^(dom|lun|mar|mi[ée]|jue|vie|s[áa]b)/i,
	wide: /^(domingo|lunes|martes|mi[ée]rcoles|jueves|viernes|s[áa]bado)/i,
	}
	const parseDayPatterns = {
	narrow: [/^d/i, /^l/i, /^m/i, /^m/i, /^j/i, /^v/i, /^s/i] as const,
	any: [/^do/i, /^lu/i, /^ma/i, /^mi/i, /^ju/i, /^vi/i, /^sa/i] as const,
	}