Remove x-data-spreadsheet, as it has unaddressed vulnerabilities

Dependabot reports that
> All versions of package x-data-spreadsheet are vulnerable to
> Cross-site Scripting (XSS) due to missing sanitization of values
> inserted into the cells.
(up to current version 1.1.9.)

Note that this issue reports an XSS issue:
myliang/x-spreadsheet#580
With this fixing PR which has not been merged:
myliang/x-spreadsheet#581

Also, some issues may have been fixed, but not released,
as this issue complains that there hasn't been a release in years
despite unreleased fixes:
myliang/x-spreadsheet#632

The package also depends on the discontinued opencollective
package, which brings additional problematic dependencies.

Author: barnardb

examples.yaml

@@ -202,12 +202,4 @@ handlers:
       - query: "layout=e/m&e=edit:$data&m=map:$data&$data=https://raw.githubusercontent.com/programmiersportgruppe/flexivis/master/docs/samples/berlin-walk.json"
         delay: 8000
 
-  table:
-    prefixes: ["table"]
-    title: "Table Editor"
-    description: |
-      Allows editing multiple CSV data sources in a spreadsheet. Changes made are broadcasted automatically when changes are introduced.
-    examples:
-      - query: "layout=tables/textA/textB&textA=text:$a&textB=text:$b&tables=table:$a;$b&$a=inline:x,y,z&$b=inline:a,b,c"
-
   # TODO: Deal with README, which isn't documented here. Arguably it shouldn't be a named view handler.