add issue template in .gitlab folder

.gitlab/issue_templates/Merchant.md

+#### What's the name of your business?
+*<write here>*
+
+#### What's the URL of the website? *referral links and trackers are not accepted*
+*<write here>*
+
+#### Write a short description of your business/service (in few words)
+*<write here>*
+
+#### Is it specified somewhere on the website that you accept Monero?
+
+- [ ] Yes
+- [ ] No
+
+#### How do you accept Monero?
+
+- [ ] Monero integrations *(github.com/monero-integrations)*
+- [ ] Globee
+- [ ] Native wallet
+- [ ] Other payment gateaway (Coinpayments, Morphtoken, etc. *Please specify*)
+
+#### How would you categorize your business?
+
+- [ ] Exchange
+- [ ] Block Explorer
+- [ ] Payment Gateway
+- [ ] Library and Helper
+- [ ] Tool
+- [ ] Service
+- [ ] Goods
+- [ ] Entertainment
+
+#### Comment
+*<write here>*
+
+
+
+/label ~merchant ~"🔍 Needs investigation"