[Conf] Add fallback maps

conf/modules.d/mid.conf

     source = {
         url = [
             "https://maps.rspamd.com/rspamd/mid.inc.zst",
-            "$LOCAL_CONFDIR/local.d/mid.inc"
+            "$LOCAL_CONFDIR/local.d/mid.inc",
+            "fallback+file://${CONFDIR}/mid.inc"
         ];
     }
 

conf/modules.d/mime_types.conf

 mime_types {
     file = [
         "https://maps.rspamd.com/rspamd/mime_types.inc.zst",
-        "${DBDIR}/mime_types.inc.local"
+        "${DBDIR}/mime_types.inc.local",
+        "fallback+file://${CONFDIR}/mime_types.inc"
     ]
 
     # Match specific extensions to specific content types

conf/modules.d/phishing.conf

     # Make exclusions for known redirectors
     redirector_domains = [
         "https://maps.rspamd.com/rspamd/redirectors.inc.zst:REDIRECTOR_FALSE",
-        "$LOCAL_CONFDIR/local.d/redirectors.inc:LOCAL_REDIRECTOR_FALSE"
+        "$LOCAL_CONFDIR/local.d/redirectors.inc:LOCAL_REDIRECTOR_FALSE",
+        "fallback+file://${CONFDIR}/redirectors.inc:REDIRECTOR_FALSE"
     ];
 
     .include(try=true,priority=5) "${DBDIR}/dynamic/phishing.conf"

conf/modules.d/surbl.conf

 surbl {
     whitelist = [
         "https://maps.rspamd.com/rspamd/surbl-whitelist.inc.zst",
-        "${DBDIR}/surbl-whitelist.inc.local"
+        "${DBDIR}/surbl-whitelist.inc.local",
+        "fallback+file://${CONFDIR}/surbl-whitelist.inc"
     ];
     exceptions = [
         "https://maps.rspamd.com/rspamd/2tld.inc.zst",
-        "${DBDIR}/2tld.inc.local"
+        "${DBDIR}/2tld.inc.local",
+        "fallback+file://${CONFDIR}/2tld.inc"
     ];
 
     rules {

conf/modules.d/whitelist.conf

             domains = [
                 "https://maps.rspamd.com/rspamd/spf_whitelist.inc.zst",
                 "${DBDIR}/spf_whitelist.inc.local",
+                "fallback+file://${CONFDIR}/spf_whitelist.inc"
             ];
             score = -1.0
             description = "Mail comes from the whitelisted domain and has a valid SPF policy";
             domains = [
                 "https://maps.rspamd.com/rspamd/dkim_whitelist.inc.zst",
                 "${DBDIR}/dkim_whitelist.inc.local",
+                "fallback+file://${CONFDIR}/dkim_whitelist.inc"
             ];
             description = "Mail comes from the whitelisted domain and has a valid DKIM signature";
             score = -1.0
             domains = [
                 "https://maps.rspamd.com/rspamd/spf_dkim_whitelist.inc.zst",
                 "${DBDIR}/spf_dkim_whitelist.inc.local",
+                "fallback+file://${CONFDIR}/spf_dkim_whitelist.inc"
             ];
             score = -3.0;
             description = "Mail comes from the whitelisted domain and has valid SPF and DKIM policies";
             domains = [
                 "https://maps.rspamd.com/rspamd/dmarc_whitelist.inc.zst",
                 "${DBDIR}/dmarc_whitelist.inc.local",
+                "fallback+file://${CONFDIR}/dmarc_whitelist.inc"
             ];
             score = -7.0;
             description = "Mail comes from the whitelisted domain and has valid DMARC and DKIM policies";

test/functional/configs/mime_types.conf

 mime_types {
-    file = "https://maps.rspamd.com/rspamd/mime_types.inc.zst";
+    file = [
+      "https://maps.rspamd.com/rspamd/mime_types.inc.zst",
+      "fallback+file://${TESTDIR}/../../../conf/mime_types.inc"
+     ];
     extension_map {
         html = "text/html";
         txt [