Fix footer links

[XhmikosR]

Fix discord footer link and remove trailing slash from repo URL

[shields-ci]

	Messages
📖	✨ Thanks for your contribution to Shields, @XhmikosR!

Generated by 🚫 dangerJS against 7ce4041

[paulmelnikow]

Nice one, thanks!

[shields-deployment]

This pull request was merged to master branch. This change is now waiting for deployment, which will usually happen within a few days. Stay tuned by joining our #ops channel on Discord!

After deployment, changes are copied to gh-pages branch:

[XhmikosR]

@paulmelnikow: there's another issue but I don't know where the cause is.

C:\Users\XhmikosR\Desktop>curl -ILl https://shields.io/category/coverage
HTTP/2 301
server: github.com
content-type: text/html
location: http://shields.io/category/coverage/
access-control-allow-origin: *
expires: Thu, 28 Feb 2019 17:03:47 GMT
cache-control: max-age=600
x-github-request-id: A6C0:7DE8:1FA40D:28C77D:5C78121B
accept-ranges: bytes
date: Thu, 28 Feb 2019 16:53:48 GMT
via: 1.1 varnish
age: 0
x-served-by: cache-lcy19243-LCY
x-cache: MISS
x-cache-hits: 0
x-timer: S1551372828.935303,VS0,VE78
vary: Accept-Encoding
x-fastly-request-id: 18cda7dd7a4e49ae4c6ca668e868c4b67b4dda12
content-length: 178

HTTP/1.1 301 Moved Permanently
Server: github.com
Content-Type: text/html
Location: https://shields.io/category/coverage/
X-GitHub-Request-Id: 3884:6DFB:3557EF:44E926:5C78121C
Content-Length: 178
Accept-Ranges: bytes
Date: Thu, 28 Feb 2019 16:53:48 GMT
Via: 1.1 varnish
Age: 0
Connection: keep-alive
X-Served-By: cache-lcy19251-LCY
X-Cache: MISS
X-Cache-Hits: 0
X-Timer: S1551372828.158699,VS0,VE76
Vary: Accept-Encoding
X-Fastly-Request-ID: 0da254706096c015b87fb989bb2074601c43beb4

HTTP/2 200
server: github.com
content-type: text/html; charset=utf-8
last-modified: Thu, 28 Feb 2019 00:11:22 GMT
etag: "5c77272a-9b87"
access-control-allow-origin: *
expires: Thu, 28 Feb 2019 17:03:48 GMT
cache-control: max-age=600
x-github-request-id: 8094:10BF:1D3DAB:25E798:5C78121C
accept-ranges: bytes
date: Thu, 28 Feb 2019 16:53:48 GMT
via: 1.1 varnish
age: 0
x-served-by: cache-lcy19243-LCY
x-cache: MISS
x-cache-hits: 0
x-timer: S1551372828.341464,VS0,VE75
vary: Accept-Encoding
x-fastly-request-id: 074f5f86ea3943959ada76becd15069da24c88d4
content-length: 39815

See the 2 redirects? It happens for all category links.