fix: use Symbol.for to make sure two concurrent versions of ts-pattern are compatible with one-another

Author: gvergnaud

src/internals/symbols.ts

@@ -13,17 +13,17 @@
  * @internal
  */
 
-export const matcher = Symbol('@ts-pattern/matcher');
+export const matcher = Symbol.for('@ts-pattern/matcher');
 export type matcher = typeof matcher;
 
-export const unset = Symbol('@ts-pattern/unset');
+export const unset = Symbol.for('@ts-pattern/unset');
 export type unset = typeof unset;
 
-export const isVariadic = Symbol('@ts-pattern/isVariadic');
+export const isVariadic = Symbol.for('@ts-pattern/isVariadic');
 export type isVariadic = typeof isVariadic;
 
 export const anonymousSelectKey = '@ts-pattern/anonymous-select-key';
 export type anonymousSelectKey = typeof anonymousSelectKey;
 
-export const override = Symbol('@ts-pattern/override');
+export const override = Symbol.for('@ts-pattern/override');
 export type override = typeof override;