Remove "2.0" from Labtool in navigation menu

[mjaakko]

Short description

DoD

I have:

• [x] added actual code.
• [x] produced clean code that passes ESLint.
• [x] code that actually does what it should.
• [ ] documented the code or added documentation to the wiki.
• [ ] added or modified test(s).
• [x] test(s) that actually pass.
• [x] works in trunk branch

[gotonode]

Labtool 2.0 still shows on the mock login page, but this is a non-issue.