Fix serializing iden as a value in ALTER TYPE ... RENAME TO ... statements (#924)

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## PR Info

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- Closes #898

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## New Features

- [ ] <!-- what are the new features? -->

## Bug Fixes

- [x] Fix serializing iden as a value in `ALTER TYPE ... RENAME TO ...`
statements

## Breaking Changes

- [ ] <!-- any change in behaviour or method signature? is it backward
compatible? -->

## Changes

- [ ] <!-- any other non-breaking changes to the codebase -->

Author: Huliiiiii

src/backend/postgres/types.rs

@@ -113,7 +113,7 @@ impl PostgresQueryBuilder {
             }
             TypeAlterOpt::Rename(new_name) => {
                 write!(sql, " RENAME TO ").unwrap();
-                self.prepare_value(&new_name.to_string().into(), sql);
+                self.prepare_iden(new_name, sql);
             }
             TypeAlterOpt::RenameValue(existing, new_name) => {
                 write!(sql, " RENAME VALUE ").unwrap();

tests/postgres/types.rs

@@ -141,7 +141,7 @@ fn alter_4() {
             .name(Font::Table)
             .rename_to("typeface")
             .to_string(PostgresQueryBuilder),
-        r#"ALTER TYPE "font" RENAME TO 'typeface'"#
+        r#"ALTER TYPE "font" RENAME TO "typeface""#
     )
 }
 
@@ -163,6 +163,6 @@ fn alter_6() {
             .name(("schema", Font::Table))
             .rename_to("typeface")
             .to_string(PostgresQueryBuilder),
-        r#"ALTER TYPE "schema"."font" RENAME TO 'typeface'"#
+        r#"ALTER TYPE "schema"."font" RENAME TO "typeface""#
     )
 }