BB2-5048: Update node

[JamesDemeryNava]

JIRA Ticket:
BB2-5048

What Does This PR Do?

Updates the node version in the server/Dockerfile to address security vulnerabilities

What Should Reviewers Watch For?

If you're reviewing this PR, please check for these things in particular:

Validation

• Build the project with docker-compose up -d
• exec into the server image, run node -v, confirm you see v26.7.0
• Go through an auth flow at localhost:3000 and make sure that works

[sb-DarenDean]

G2G! Have another eng review and approve. Thanks.

[ryan-morosa]

It works as described! Nice job! I think you'll have to rerun the pipeline maybe

[JamesDemeryNava]

@sb-DarenDean the client Dockerfile has the same node version, going to update that here as well.

[ryan-morosa]

Everything still looks good to me!