Fix nationalmap/about page & logos to redirect to GA's NationalMap page

[AnaBelgun]

• when users click on NationalMap About page button, they are correctly redirected to https://www.ga.gov.au/scientific-topics/national-location-information/nationalmap
• the url https://nationalmap.gov.au/about points to an old About page
• the NationalMap logo and branding points to the old about page

TODO

• nationalmap/about redirects to https://www.ga.gov.au/scientific-topics/national-location-information/nationalmap
• redirect Logos to https://www.ga.gov.au/scientific-topics/national-location-information/nationalmap

[nf-s]

• https://github.com/TerriaJS/saas-catalogs-public/pull/365

[AnaBelgun]

not required any longer