Docs: Mention queryparam function (#54526)

* Update data-link-variables.md

Add queryparam function and tables of output to match the other listed variables

* Update docs/sources/linking/data-link-variables.md

Co-authored-by: Christopher Moyer <35463610+chri2547@users.noreply.github.com>

* Add r4j4h's suggestions to the new documentation space with some partial changes to the wording

* Add r4j4h's suggestions to the new documentation space with some partial changes to the wording

* mockery generated code as it is on main

* simplify changes in docs and go straight to the point

Co-authored-by: Jasmine Hegman <jasmine@jhegman.com>
Co-authored-by: Christopher Moyer <35463610+chri2547@users.noreply.github.com>

docs/sources/panels/configure-data-links/index.md

@@ -66,9 +66,15 @@ Value-specific variables are available under `__value` namespace:
 
 When linking to another dashboard that uses template variables, select variable values for whoever clicks the link.
 
-`${myvar:queryparam}` - where `myvar` is a name of the template variable that matches one in the current dashboard that you want to use.
+`${var-myvar:queryparam}` - where `var-myvar` is the name of the template variable that matches one in the current dashboard that you want to use.
 
-If you want to add all of the current dashboard's variables to the URL, then use `__all_variables`.
+| Variable state           | Result in the created URL           |
+| ------------------------ | ----------------------------------- |
+| selected one value       | `var-myvar=value1`                  |
+| selected multiple values | `var-myvar=value1&var-myvar=value2` |
+| selected `All`           | `var-myvar=All`                     |
+
+If you want to add all of the current dashboard's variables to the URL, then use `${__all_variables}`.
 
 ## Data links