There is an updated pull request by classabbyamp against master on the void-packages repository

https://github.com/classabbyamp/void-packages xshellcheck
https://github.com/void-linux/void-packages/pull/43949

lint templates with shellcheck
<!-- Uncomment relevant sections and delete options which are not applicable -->

#### Testing the changes
- I tested the changes in this PR: **YES**

we may want to disable some warnings by default, currently these warnings are raised:

| count | code   | wiki link                              |
|------:|:-------|:---------------------------------------|
|  8516 | SC2086 | https://www.shellcheck.net/wiki/SC2086 |
|   499 | SC2034 | https://www.shellcheck.net/wiki/SC2034 |
|   287 | SC2016 | https://www.shellcheck.net/wiki/SC2016 |
|   156 | SC2091 | https://www.shellcheck.net/wiki/SC2091 |
|   144 | SC2046 | https://www.shellcheck.net/wiki/SC2046 |
|   103 | SC2035 | https://www.shellcheck.net/wiki/SC2035 |
|    83 | SC2154 | https://www.shellcheck.net/wiki/SC2154 |
|    75 | SC2209 | https://www.shellcheck.net/wiki/SC2209 |
|    73 | SC2231 | https://www.shellcheck.net/wiki/SC2231 |
|    59 | SC2155 | https://www.shellcheck.net/wiki/SC2155 |
|    53 | SC2044 | https://www.shellcheck.net/wiki/SC2044 |
|    39 | SC2295 | https://www.shellcheck.net/wiki/SC2295 |
|    36 | SC2115 | https://www.shellcheck.net/wiki/SC2115 |
|    28 | SC2166 | https://www.shellcheck.net/wiki/SC2166 |
|    22 | SC2185 | https://www.shellcheck.net/wiki/SC2185 |
|    21 | SC2103 | https://www.shellcheck.net/wiki/SC2103 |
|    19 | SC1091 | https://www.shellcheck.net/wiki/SC1091 |
|    13 | SC2043 | https://www.shellcheck.net/wiki/SC2043 |
|    12 | SC2162 | https://www.shellcheck.net/wiki/SC2162 |
|    12 | SC2001 | https://www.shellcheck.net/wiki/SC2001 |
|    10 | SC2129 | https://www.shellcheck.net/wiki/SC2129 |
|     9 | SC2098 | https://www.shellcheck.net/wiki/SC2098 |
|     9 | SC2038 | https://www.shellcheck.net/wiki/SC2038 |
|     7 | SC2031 | https://www.shellcheck.net/wiki/SC2031 |
|     6 | SC2090 | https://www.shellcheck.net/wiki/SC2090 |
|     6 | SC2013 | https://www.shellcheck.net/wiki/SC2013 |
|     5 | SC2140 | https://www.shellcheck.net/wiki/SC2140 |
|     5 | SC2097 | https://www.shellcheck.net/wiki/SC2097 |
|     5 | SC2045 | https://www.shellcheck.net/wiki/SC2045 |
|     4 | SC2261 | https://www.shellcheck.net/wiki/SC2261 |
|     4 | SC2153 | https://www.shellcheck.net/wiki/SC2153 |
|     4 | SC2015 | https://www.shellcheck.net/wiki/SC2015 |
|     3 | SC2269 | https://www.shellcheck.net/wiki/SC2269 |
|     3 | SC2223 | https://www.shellcheck.net/wiki/SC2223 |
|     3 | SC2196 | https://www.shellcheck.net/wiki/SC2196 |
|     3 | SC2089 | https://www.shellcheck.net/wiki/SC2089 |
|     3 | SC2061 | https://www.shellcheck.net/wiki/SC2061 |
|     3 | SC2059 | https://www.shellcheck.net/wiki/SC2059 |
|     3 | SC2030 | https://www.shellcheck.net/wiki/SC2030 |
|     3 | SC2004 | https://www.shellcheck.net/wiki/SC2004 |
|     3 | SC2002 | https://www.shellcheck.net/wiki/SC2002 |
|     2 | SC2237 | https://www.shellcheck.net/wiki/SC2237 |
|     2 | SC2125 | https://www.shellcheck.net/wiki/SC2125 |
|     2 | SC2094 | https://www.shellcheck.net/wiki/SC2094 |
|     2 | SC2005 | https://www.shellcheck.net/wiki/SC2005 |
|     1 | SC2222 | https://www.shellcheck.net/wiki/SC2222 |
|     1 | SC2221 | https://www.shellcheck.net/wiki/SC2221 |
|     1 | SC2207 | https://www.shellcheck.net/wiki/SC2207 |
|     1 | SC2168 | https://www.shellcheck.net/wiki/SC2168 |
|     1 | SC2145 | https://www.shellcheck.net/wiki/SC2145 |
|     1 | SC2144 | https://www.shellcheck.net/wiki/SC2144 |
|     1 | SC2102 | https://www.shellcheck.net/wiki/SC2102 |
|     1 | SC2100 | https://www.shellcheck.net/wiki/SC2100 |
|     1 | SC2078 | https://www.shellcheck.net/wiki/SC2078 |
|     1 | SC2068 | https://www.shellcheck.net/wiki/SC2068 |
|     1 | SC2012 | https://www.shellcheck.net/wiki/SC2012 |
|     1 | SC2010 | https://www.shellcheck.net/wiki/SC2010 |
|     1 | SC1090 | https://www.shellcheck.net/wiki/SC1090 |

[ci skip]

A patch file from https://github.com/void-linux/void-packages/pull/43949.patch is attached