prisma: Introspection fails to generate `@relation` for many-to-many relation in MySQL

Newer reproduction here: https://github.com/prisma/prisma/issues/14668#issuecomment-1755468605

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Bug description

Introspection (db pull) fails to generate @relation for relations between tables, that are using compound keys.

How to reproduce

1. Create schema from SQL bellow
2. run npx prisma db pull
3. See error in relation between tables

Expected behavior

The resulting schema should create @relation with the correct fields.

Generated:

@relation(fields: [offerID], references: [offerID], onDelete: Cascade, onUpdate: NoAction)

Correct:

@relation(fields: [offerID, periodID, carrierID], references: [offerID, periodID, carrierID], onDelete: Cascade, onUpdate: NoAction)

Prisma information

CREATE TABLE `nabzak` (
  `offerID` smallint unsigned NOT NULL,
  `periodID` smallint unsigned NOT NULL,
  `carrierID` int NOT NULL,
  PRIMARY KEY (`offerID`, `periodID`, `carrierID`),
  CONSTRAINT `nabzak_zaknos` FOREIGN KEY (`offerID`, `periodID`, `carrierID`) REFERENCES `CarrierInPeriod` (`offerID`, `periodID`, `carrierID`) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=cp1250 COLLATE=cp1250_czech_cs;

CREATE TABLE `CarrierInPeriod` (
  `offerID` smallint unsigned NOT NULL,
  `periodID` smallint unsigned NOT NULL,
  `carrierID` int NOT NULL,
  PRIMARY KEY (`offerID`, `periodID`, `carrierID`)
) ENGINE=InnoDB DEFAULT CHARSET=cp1250 COLLATE=cp1250_czech_cs;

Environment & setup

• OS: Windows
• Database: MySQL
• Node.js version: v16.13.2

Prisma Version

prisma                  : 4.1.1
@prisma/client          : 4.1.1
Current platform        : windows
Query Engine (Node-API) : libquery-engine 8d8414deb360336e4698a65aa45a1fbaf1ce13d8 (at node_modules\@prisma\engines\query_engine-windows.dll.node)
Migration Engine        : migration-engine-cli 8d8414deb360336e4698a65aa45a1fbaf1ce13d8 (at node_modules\@prisma\engines\migration-engine-windows.exe)
Introspection Engine    : introspection-core 8d8414deb360336e4698a65aa45a1fbaf1ce13d8 (at node_modules\@prisma\engines\introspection-engine-windows.exe)
Format Binary           : prisma-fmt 8d8414deb360336e4698a65aa45a1fbaf1ce13d8 (at node_modules\@prisma\engines\prisma-fmt-windows.exe)
Default Engines Hash    : 8d8414deb360336e4698a65aa45a1fbaf1ce13d8
Studio                  : 0.469.0
Preview Features        : interactiveTransactions

Extracted from https://github.com/prisma/prisma/issues/14648#issuecomment-1205224365