Space before the physical unit

If you type a numeric literal with a physical unit, there should be a space between the number and the unit.

VHDL
T := 25ns;  -- ILLEGAL, but accepted by ModelSim
T := 25 ns; -- OK; according to VHDL language standard

Mentor Graphics’ ModelSim and QuestaSim accept the former (illegal) version. As a result, some VHDL designers got used to writing the incorrect version, producing code that is not portable to other simulators. Sigasi accepts the ModelSim-style physical literals but warns about this (rule 47).

Rule configuration

This rule can be disabled for your project, or its severity and parameters can be modified in the project linting settings. Alternatively, it can be manually configured using one of the following templates, depending on the type of project you use.

For Modular Projects, add these entries to your project's .sigasi/settings.json settings file. To scope the settings to a specific folder or file instead of the whole project, place them inside an @override block; to scope them to a specific target, place them inside a @targets block.
JSONC
```
{
    "vhdl.rules.47.severity": "{ERROR|WARNING|INFO|IGNORE}"
}
```
For Classic Projects, add the VHDL lines to .settings/com.sigasi.hdt.vhdl.linting.prefs and the Verilog/SystemVerilog lines to .settings/com.sigasi.hdt.verilog.linting.prefs:
PREFS
```
47/severity/${path}={error|warning|info|ignore}
```