Sync the test path with test1515. If fixes the test when the perl tool
resides on a path with spaces in it. E.g. when using the perl from Git
for Windows. This is a workaround, there may be a better fix this
type of issue.
Similar fix for test1515: 38b055446ae46e4568328fa90e96a87fe71c56a7
Failure:
```
test 1516...[caching of manual libcurl DNS entries after dead connection]
lib1515.exe returned 3, when expecting 0
1516: exit FAILED
=== Start of file stderr1516
Test: lib1515
[...]
17:59:32.390000 == Info: Expire cleared
request http://testserver.example.com:63621/C:/Program Files/Git/path/15160001 failed with 3
Test ended with result 3
=== End of file stderr1516
```
Ref: https://github.com/curl/curl/actions/runs/13184790755/job/36804217128?pr=16217#step:13:2805Closes#16223
Fix for bug #1303 (030a2b8cb) was not complete.
libcurl still pruned DNS entries added manually
after detecting a dead connection. This test
checks such behavior.