tos3to4: fix postrm script error - trying to execute luci-app-squid
The current `tos3to4` package causes the following error:
```
INFO:Running postrm of tos3to4
/usr/lib/opkg/info//tos3to4.postrm: line 1: luci-app-squid: not found
/usr/lib/opkg/info//tos3to4.postrm: line 20: syntax error: unexpected "}"
INFO:Running postrm of cznic-repo-keys-test
INFO:Cleaning up control files
ERROR:Failed operations:
tos3to4/postrm: /usr/lib/opkg/info//tos3to4.postrm: line 1: luci-app-squid: not found
/usr/lib/opkg/info//tos3to4.postrm: line 20: syntax error: unexpected "}"
```
This is because of the use of backticks in the string in the shell script being interpreted as evaluation. A patch is attached; I'd send a MR but I'm not allowed to fork the repository (could I/we please get that access? it'd make submitting fixes much simpler).
[fix-backticks.patch](/uploads/b17770dbbc891ebbd80d0e012d1b6944/fix-backticks.patch)
issue