Fix overly long related post titles

[kean]

Description

Fix CMM-983: Very long titles can be abused to show unwanted content on people's sites

Before / After

[wpmobilebot]

📲 You can test the changes from this Pull Request in Jetpack by scanning the QR code below to install the corresponding build.

	App Name	Jetpack
	Configuration	Release-Alpha
	Build Number	29914
	Version	PR #25011
	Bundle ID	com.jetpack.alpha
	Commit	2117768
	Installation URL	708ekpmkelhfg

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[crazytonyli]

Hey @kean, I think we want to include the fixes in the 26.5 release. Can you change this PR's base branch?

[kean]

I rebase it and made a couple of tiny design tweaks to make images smaller and tags stand out a bit less.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[wpmobilebot]

📲 You can test the changes from this Pull Request in WordPress by scanning the QR code below to install the corresponding build.

	App Name	WordPress
	Configuration	Release-Alpha
	Build Number	29914
	Version	PR #25011
	Bundle ID	org.wordpress.alpha
	Commit	2117768
	Installation URL	68l8eet58lk98

Automatticians: You can use our internal self-serve MC tool to give yourself access to those builds if needed.