(core) Fix number parsing/formatting tests after updates to node version and locales

Summary:
The en-ZA locale was recently updated: https://github.com/nodejs/node/issues/48120

This caused test failures which I was happy about, until I saw af-ZA is still using the old separators.

Test Plan: Tests failed locally when using the latest node 18, then passed after this change.

Reviewers: jarek

Reviewed By: jarek

Differential Revision: https://phab.getgrist.com/D4079

test/common/NumberParse.ts

@@ -153,10 +153,10 @@ describe("NumberParse", function() {
     check("  123 456 789,123", 123456789.123);  // normal space
     check("  123 456 789,123", 123456789.123);  // NBSP
 
-    formatter = Intl.NumberFormat("en-ZA", {useGrouping: true});
+    formatter = Intl.NumberFormat("af-ZA", {useGrouping: true});
     assert.equal(formatter.format(123456789.123), '123 456 789,123');
 
-    parser = new NumberParse("en-ZA", "ZAR");
+    parser = new NumberParse("af-ZA", "ZAR");
 
     assert.equal(parser.digitGroupSeparator, " ");
     assert.equal(parser.digitGroupSeparatorCurrency, " ");

test/common/ValueFormatter.ts

@@ -115,7 +115,7 @@ describe("ValueFormatter", function() {
       assert.equal(fmt({numMode: 'currency'}, 0.1234567, {locale: 'fr-BE'}), '0,12 €');
       assert.equal(fmt({numMode: 'currency', maxDecimals: 0}, 12.34567, {locale: 'en-GB'}), '£12.35');
       assert.equal(fmt({numMode: 'currency', decimals: 0, maxDecimals: 0}, 12.34567, {locale: 'en-IE'}), '€12');
-      assert.equal(fmt({numMode: 'currency'}, 1.015e-8, {locale: 'en-ZA'}), 'R 0,00');
+      assert.equal(fmt({numMode: 'currency'}, 1.015e-8, {locale: 'af-ZA'}), 'R 0,00');
       assert.equal(fmt({numMode: 'currency', maxDecimals: 10}, 1.015e-8, {locale: 'en-CA'}), '$0.0000000102');
       assert.equal(fmt({numMode: 'currency'}, -1.015e-8, {locale: 'nl-BE'}), '€ -0,00');
 
@@ -133,7 +133,7 @@ describe("ValueFormatter", function() {
       assert.equal(
         fmt({numMode: 'currency', decimals: 0, maxDecimals: 0}, 12.34567, {locale: 'en-IE', currency: 'SGD'}),
         '$12');
-      assert.equal(fmt({numMode: 'currency'}, 1.015e-8, {locale: 'en-ZA', currency: 'HKD'}), '$0,00');
+      assert.equal(fmt({numMode: 'currency'}, 1.015e-8, {locale: 'af-ZA', currency: 'HKD'}), '$0,00');
       assert.equal(
         fmt({numMode: 'currency', maxDecimals: 10}, 1.015e-8, {locale: 'en-CA', currency: 'RUB'}),
         '₽0.0000000102');