[devtools] Set dumb value for postgres's db-host to avoid unexpected connection to a local server Currently, if something goes wrong (eg config built before call to startpgcluster) while a pg server is running on localhost, it may connect to this server and run the test in there unexepectedly.

Release notes
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.. toctree::
    :maxdepth: 1

    3.22
    3.21
    3.20
    3.19
    3.18
    3.17
    3.16
    3.15
    3.14