Don't try to run multiple insert queries at once

SQLite's default query interface ignores anything after the first
semicolon in a query. This is actually quite common behavior in database
drivers, especially when dealing with code paths for prepared statements
(which we are). While this should only affect SQLite, as I'm not aware
of any drivers which don't support multi-insert. Even if this does
affect other third party drivers though, I'd prefer not to assume that
more than one query can be executed per call to `execute`.

Fixes #26948.
Close #27242.

activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb

@@ -996,15 +996,13 @@ def dump_schema_information #:nodoc:
       def insert_versions_sql(versions) # :nodoc:
         sm_table = ActiveRecord::Migrator.schema_migrations_table_name
 
-        if supports_multi_insert?
+        if versions.is_a?(Array)
           sql = "INSERT INTO #{sm_table} (version) VALUES\n"
           sql << versions.map { |v| "('#{v}')" }.join(",\n")
           sql << ";\n\n"
           sql
         else
-          versions.map { |version|
-            "INSERT INTO #{sm_table} (version) VALUES ('#{version}');"
-          }.join "\n\n"
+          "INSERT INTO #{sm_table} (version) VALUES ('#{versions}');"
         end
       end
 
@@ -1042,7 +1040,13 @@ def assume_migrated_upto_version(version, migrations_paths)
           if (duplicate = inserting.detect { |v| inserting.count(v) > 1 })
             raise "Duplicate migration #{duplicate}. Please renumber your migrations to resolve the conflict."
           end
-          execute insert_versions_sql(inserting)
+          if supports_multi_insert?
+            execute insert_versions_sql(inserting)
+          else
+            inserting.each do |v|
+              execute insert_versions_sql(v)
+            end
+          end
         end
       end