[4.0] Cast XML element as string

[SharkyKZ]

Summary of Changes

Missed these in #27194. Casts XML element as string so strict comparison works properly.

Testing Instructions

Code review.
Or edit System - SEF plugin. In canonical domain field enter a URL without protocol (e.g. localhost).

Expected result

Value saved as http://localhost.

Actual result

Saving fails with error:

Invalid URL: URL schema is missing in localhost. Please add one of the following at the beginning: http, https, ftp, ftps, gopher, mailto, news, prospero, telnet, rlogin, sftp, tn3270, wais, mid, cid, nntp, tel, urn, ldap, file, fax, modem, git.

Documentation Changes Required

No.

[Quy]

I have tested this item ✅ successfully on 62161bf

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[jwaisner]

I have tested this item ✅ successfully on 62161bf

Testing of PR is good.

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[jwaisner]

RTC

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