[update] snippets names in the new docs

Author: mafanya23

docs/api/spreadsheet_addformula_method.md

@@ -50,6 +50,6 @@ spreadsheet.parse([
 
 **Change log:** Added in v6.0
 
-**Related sample:** [Spreadsheet. Custom formula](https://snippet.dhtmlx.com/wvxdlahp)
+**Related sample:** [Spreadsheet. Add custom formula](https://snippet.dhtmlx.com/wvxdlahp)
 
 **Related articles:** [Formulas and functions](/functions/#custom-formulas)

docs/customization.md

@@ -257,7 +257,7 @@ spreadsheet.toolbar.data.add(
 spreadsheet.parse(dataset);
 ~~~
 
-**Related sample:** [Spreadsheet. Custom font size](https://snippet.dhtmlx.com/tffbf11g)
+**Related sample:** [Spreadsheet. Set custom font size](https://snippet.dhtmlx.com/tffbf11g)
 
 ## Menu
 

docs/functions.md

@@ -1385,4 +1385,4 @@ spreadsheet.parse([
 The handler function must be synchronous. Using `Promise` or `fetch` inside the function is not allowed.
 :::
 
-**Related sample:** [Spreadsheet. Custom formula](https://snippet.dhtmlx.com/wvxdlahp)
+**Related sample:** [Spreadsheet. Add custom formula](https://snippet.dhtmlx.com/wvxdlahp)