Ensure BigDecimals are not binary-encoded

In Ruby 2.7, `BigDecimal#to_s` generates ASCII-8BIT-encoded strings.
We don't want those to get hex-encoded in the generated SQL.

Author: olefriis

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

@@ -16,7 +16,10 @@ def quote(value)
         when false      then quoted_false
         when nil        then "NULL"
         # BigDecimals need to be put in a non-normalized form and quoted.
-        when BigDecimal then value.to_s("F")
+        # Additionally, for Ruby 2.7, the string returned by `to_s` is ASCII-8BIT.
+        # We want to avoid that, as that will cause the string to be quoted as
+        # binary. It is safe to force the encoding to US-ASCII.
+        when BigDecimal then value.to_s("F").force_encoding(Encoding::US_ASCII)
         when Numeric then value.to_s
         when Type::Binary::Data then quoted_binary(value)
         when Type::Time::Value then "'#{quoted_time(value)}'"

activerecord/lib/active_record/connection_adapters/mysql/quoting.rb

@@ -23,10 +23,13 @@ def cast_bound_value(value)
           case value
           when Rational
             value.to_f.to_s
+          when BigDecimal
+            # For Ruby 2.7, the string returned by `to_s` is ASCII-8BIT.
+            # We want to avoid that, as that will cause the string to be quoted as
+            # binary. It is safe to force the encoding to US-ASCII.
+            value.to_s("F").force_encoding(Encoding::US_ASCII)
           when Numeric
             value.to_s
-          when BigDecimal
-            value.to_s("F")
           when true
             "1"
           when false