Adds specs and fix for \s after separator

[l-schirrmeister]

We have in our .env-file an entry with = as separator followed by a \s and a quoted value including # in this way:

SECRET_PASSWORD              = 'foo#bar234#'

Parsing it leads to the unfortunate cutting after the #:

env("SECRET_PASSWORD              = 'foo#bar234#'")
=> {"SECRET_PASSWORD"=>"'foo"}

This fix will let it parse correctly:

env("SECRET_PASSWORD              = 'foo#bar234#'")
=> {"SECRET_PASSWORD"=>"foo#bar234#"}

[vermaxik]

Thank for MR @l-schirrmeister !
We have the same issue since 2.5 and fixated an app with 2.4 version.

[cadwallion]

Thank you for the contribution! I'll be cutting a patch-level release shortly with this.

[promisedlandt]

Good job @l-schirrmeister :p