Fix CSP Always being Enabled unless in debug mode.

[misilot]

Description

CSP is always enabled unless debug is set to false.
Change: if ((config('app.debug')!='true') || (config('app.enable_csp')=='true')) {
to:
if ((config('app.debug')!='true') && (config('app.enable_csp')=='true')) {

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

• Have debug = false and enable_csp = false, look for CSP Header in response from server (it will be there)
• Apply patch
• Have debug = false and enable_csp = false, look for CSP header in response (it won't be there)

Checklist:

• I have read the Contributing documentation available here: https://snipe-it.readme.io/docs/contributing-overview
• I have formatted this PR according to the project guidelines: https://snipe-it.readme.io/docs/contributing-overview#pull-request-guidelines
• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes