removed extra spaces that were causing integration issues (#431)

The extra spaces that were hard to see were causing integrations to
fail.

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **Documentation**
* Updated formatting and indentation in LTI 1.3 Canvas integration
documentation for improved readability.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: shajason

source/instructors/admin/integration/lti1-3Canvas.rst

@@ -223,7 +223,7 @@ Updating the fields in Platform Information
    .. code-tab:: text
       :caption: Platform ID
 
-       https://canvas.instructure.com
+      https://canvas.instructure.com
 
 
 
@@ -240,7 +240,7 @@ Updating the fields in Platform Information
    .. code-tab:: text
       :caption: Public Keyset URL
 
-       https://[CANVAS DOMAIN]/api/lti/security/jwks
+      https://[CANVAS DOMAIN]/api/lti/security/jwks
 
 6. **Access Token URL:**
 
@@ -249,7 +249,7 @@ Updating the fields in Platform Information
    .. code-tab:: text
       :caption: Access Token URL
 
-       https://[CANVAS DOMAIN]/login/oauth2/token
+      https://[CANVAS DOMAIN]/login/oauth2/token
 
 7. **Authentication Request URL:**
 
@@ -258,7 +258,7 @@ Updating the fields in Platform Information
    .. code-tab:: text
       :caption: Authentication Request URL
 
-       https://[CANVAS DOMAIN]/api/lti/authorize_redirect
+      https://[CANVAS DOMAIN]/api/lti/authorize_redirect
 
 8. Click **Create**