docs(public_reference): add Caylent as a public reference (#4822)

Adding Caylent as public ref

Author: leandrodamascena

README.md

@@ -56,6 +56,7 @@ The following companies, among others, use Powertools:
 * [Brsk](https://www.brsk.co.uk/)
 * [BusPatrol](https://buspatrol.com/)
 * [Capital One](https://www.capitalone.com/)
+* [Caylent](https://caylent.com/)
 * [CPQi (Exadel Financial Services)](https://cpqi.com/)
 * [CloudZero](https://www.cloudzero.com/)
 * [CyberArk](https://www.cyberark.com/)

docs/index.md

@@ -433,6 +433,9 @@ Knowing which companies are using this library is important to help prioritize t
 [**Capital One**](https://www.capitalone.com/){target="_blank" rel="nofollow"}
 { .card }
 
+[**Caylent**](https://caylent.com/){target="_blank" rel="nofollow"}
+{ .card }
+
 [**CPQi (Exadel Financial Services)**](https://cpqi.com/){target="_blank" rel="nofollow"}
 { .card }