feat(logger/loki): Support for tenants when running Loki in multi-tenant mode (#477)

imports/logger/server.lua

@@ -131,6 +131,7 @@ if service == 'loki' then
     local lokiUser = GetConvar('loki:user', '')
     local lokiPassword = GetConvar('loki:password', GetConvar('loki:key', ''))
     local lokiEndpoint = GetConvar('loki:endpoint', '')
+    local lokiTenant = GetConvar('loki:tenant', '')
     local startingPattern = '^http[s]?://'
     local headers = {
         ['Content-Type'] = 'application/json'
@@ -140,6 +141,10 @@ if service == 'loki' then
         headers['Authorization'] = getAuthorizationHeader(lokiUser, lokiPassword)
     end
 
+    if lokiTenant ~= '' then
+        headers['X-Scope-OrgID'] = lokiTenant
+    end
+
     if not lokiEndpoint:find(startingPattern) then
         lokiEndpoint = 'https://' .. lokiEndpoint
     end