In declaration review page, heading is not shown correctly when full name is not given.

[tiri39]

Bug description:
When child's only first / last name is given, heading is not shown properly in declaration review page.

Steps to reproduce:

1. Create a declaration with only first or only last name for child.
2. Navigate to the review page for that declaration.
3. Observe the heading.

Actual result:
When child's only first / last name is given, heading is- 'Birth declaration'.

Expected result:
When child's only first / last name is given, heading should be - 'Birth declaration for [child's first name/last name]

Screenshot/ Recording:

here, heading should be - 'Birth declaration for Raisa'

Tested on:
https://register.events-v2-test-environment.opencrvs.dev/v2

[makelicious]

Seems to be related to #8979. Check both while you fix this
Regression?

[cibelius]

This was merged: #9885