Port to GitHub actions & publish to Terraform registry (#39)

* Port to GitHub actions

* Fix

* Make docs terraform registry compatible

docs/resources/bitbucketserver_user.md

@@ -0,0 +1,33 @@
+# Resource: bitbucketserver_user
+
+Create a Bitbucket user.
+
+## Example Usage
+
+```hcl
+resource "bitbucketserver_user" "admin" {
+  name          = "mreynolds"
+  display_name  = "Malcolm Reynolds"
+  email_address = "browncoat@example.com"
+}
+```
+
+## Argument Reference
+
+* `name` - Required. Username of the user.
+* `display_name` - Required. User's name to display.
+* `email_address` - Required. Email address of user.
+* `password_length` - Optional. The length of the generated password on resource creation. Only applies on resource creation. Default `20`.
+
+## Attribute Reference
+
+* `initial_password` - The generated user password. Only available if password was handled on Terraform resource creation, not import.
+* `user_id` - The user ID.
+
+## Import
+
+Import a user reference via the user's name.
+
+```
+terraform import bitbucketserver_user.test mreynolds
+```