Global Variables with a literal "." in the value causes the variable to be undefined

To reproduce:
This can be reproduced using the CLI or the programmatic API. Assuming that LESS is already installed, it is most straightforward to reproduce using the CLI:

echo "body { color: @buildVersion; }" | npx lessc --global-var="buildVersion=a.hello" -

On the other hand, removing the literal period allows this to work:

echo "body { color: @buildVersion; }" | npx lessc --global-var="buildVersion=hello" -

LESS Code:

body { color: @buildVersion; }

Current behavior:
The LESS compiler throws an error that the global variable is undefined.

Expected behavior:
The LESS compiler should not throw an error and the global variable should be defined.

Environment information:

• less version: 3.5.0 - 4.1.3 (current)
• nodejs version: 16.13.2
• operating system: Windows

Appears to have been introduced in 3.5.0. Version 3.0.4 appears to be working fine.

Start by running the provided npx lessc command with and without the literal period, then compare how the --global-var value is handled through the CLI and programmatic API. Look for the global-variable parsing or resolution path and add a regression check; done means the a.hello value compiles without an undefined-variable error while the existing hello case still works.