docs: Replace RelayKit alpha version with latest

[germartinez]

Context

This PR:

• After the release of the Relay Kit including the Safe4337Pack, this PR replaces the alpha version with the latest one.

[github-actions]

Overall readability score: 56.24 (🟢 +0)

File	Readability
4337-safe-sdk.mdx	31.86 (🟢 +0)
safe-4337-pack.mdx	60.42 (🟢 +0)

View detailed metrics

🟢 - Shows an increase in readability
🔴 - Shows a decrease in readability

File	Readability	FRE	GF	ARI	CLI	DCRS
4337-safe-sdk.mdx	31.86	43.5	17.77	21.2	11.09	7.81
	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0
safe-4337-pack.mdx	60.42	34.22	8.21	11.7	14.13	6.51
	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0

Averages:

	Readability	FRE	GF	ARI	CLI	DCRS
Average	56.24	49	10.74	12.62	12.34	7.59
	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0

View metric targets

Metric	Range	Ideal score
Flesch Reading Ease	100 (very easy read) to 0 (extremely difficult read)	60
Gunning Fog	6 (very easy read) to 17 (extremely difficult read)	8 or less
Auto. Read. Index	6 (very easy read) to 14 (extremely difficult read)	8 or less
Coleman Liau Index	6 (very easy read) to 17 (extremely difficult read)	8 or less
Dale-Chall Readability	4.9 (very easy read) to 9.9 (extremely difficult read)	6.9 or less