Docs: Updates to History Mode for Apache w/ subfolder

[itsxallwater]

Reason I had issues getting this to work with the examples in the doc as currently written. It wasn't until I found this answer on Stack Overflow where things became clear. Admittedly, I'm not well versed in Apache, but I figured these amendments might better serve others in the future. Per the Stack Overflow answer it seems there was a related Vue Forum discussion which tells me the scenario is not uncommon.

What changed? I added a few specifics to the Apache example in history-mode.md and removed the trailing / in the RewriteBase example for subfolders. These adjustments mirror how I was able to get my application working when building to a different base path and deploying to Apache.

[chenkunlong]

sd

[Alanscut]

Hi @itsxallwater , could you add apacheconf after ``` to highlight it?

[itsxallwater]

Done!