deparse altered "ALTER TABLE" statement, removed ON DELETE, ON UPDATE clauses

[divyenduz]

Original query (with fingerprint 08ac274ed7e25268):

ALTER TABLE "Customer" ADD CONSTRAINT "FK_CustomerSupportRepId"
  FOREIGN KEY ("SupportRepId") REFERENCES "Employee" ("EmployeeId") ON DELETE NO ACTION ON UPDATE NO ACTION

Deparsed query (with fingerprint 7cd581c9cf34edae):

ALTER TABLE "Customer" ADD CONSTRAINT FK_CustomerSupportRepId FOREIGN KEY ( "SupportRepId" ) REFERENCES "Employee" ( "EmployeeId" );

To reproduce:

const fs = require('fs')
const { parse, deparse } = require('pgsql-parser');

async function main() {
    const stmts = parse(`
      ALTER TABLE "Customer" ADD CONSTRAINT "FK_CustomerSupportRepId"
  FOREIGN KEY ("SupportRepId") REFERENCES "Employee" ("EmployeeId") ON DELETE NO ACTION ON UPDATE NO ACTION
    `)
    const stmts2 = deparse(stmts[0])
    console.log(stmts2)
}

main()

Schema at https://github.com/prisma/database-schema-examples/tree/main/postgres/chinook

[pyramation]

those are the defaults, so they don't get printed. When I run the AST generated from the code and then to code, and back to AST, it's the same result. I'll add this snippet to the test cases and push it.