Very small addition in multi-tenancy docs

[danceb]

Within the docs for multi tenancy I would recommend to add a / in line 37 [1] after the tenant regex as:

location ~ ^/(?<t>tenant1|tenant2)/ {

instead of

location ~ ^/(?<t>tenant1|tenant2) {

Otherwise the app works also with urls like http://localhost:8080/tenant1abc/ and not only http://localhost:8080/tenant1/.

[1] https://github.com/qwc-services/qwc-services.github.io/blob/master/src/topics/MultiTenancy.md?plain=1#L37

[manisandro]

Thanks, done in 8552449