disable test_currencyAccountingMinimumIntegerDigits & test_currencyISOCodeMinimumIntegerDigits

test_currencyAccountingMinimumIntegerDigits does not work with Ubuntu
14.04's libICU and therefore we can't run it in CI.

This will be fixed with Swift 5 because Swift 5 vendors libICU which is
the right solution but too big of a change for Swift 4.2.

test_currencyISOCodeMinimumIntegerDigits has to be disabled too even
though the code does not crash on Swift 4.2.3 on Ubuntu 14.04. The
reason is that commit 3290d07 corrects
the NumberFormatting styles. Previously, currencyISOCode used to map to
`7` which is incorrect. Now it correctly maps to `8` but unfortunately
that is unsupported by 14.04's libICU...

Author: weissi

TestFoundation/TestNumberFormatter.swift

@@ -30,8 +30,6 @@ class TestNumberFormatter: XCTestCase {
             ("test_scientificMinimumIntegerDigits", test_scientificMinimumIntegerDigits),
             ("test_spellOutMinimumIntegerDigits", test_spellOutMinimumIntegerDigits),
             ("test_ordinalMinimumIntegerDigits", test_ordinalMinimumIntegerDigits),
-            ("test_currencyISOCodeMinimumIntegerDigits", test_currencyISOCodeMinimumIntegerDigits),
-            ("test_currencyAccountingMinimumIntegerDigits", test_currencyAccountingMinimumIntegerDigits),
             ("test_maximumIntegerDigits", test_maximumIntegerDigits),
             ("test_minimumFractionDigits", test_minimumFractionDigits),
             ("test_maximumFractionDigits", test_maximumFractionDigits),
@@ -345,52 +343,6 @@ class TestNumberFormatter: XCTestCase {
         XCTAssertEqual(formatter2.string(from: 42), "42nd")
     }
 
-    func test_currencyISOCodeMinimumIntegerDigits() {
-        // If .minimumIntegerDigits is set to 0 before .numberStyle change, preserve the value
-        let formatter = NumberFormatter()
-        XCTAssertEqual(formatter.minimumIntegerDigits, 0)
-        formatter.minimumIntegerDigits = 0
-        formatter.numberStyle = .currencyISOCode
-        XCTAssertEqual(formatter.minimumIntegerDigits, 0)
-        formatter.locale = Locale(identifier: "en_US")
-        XCTAssertEqual(formatter.string(from: 0), "USD.00")
-        XCTAssertEqual(formatter.string(from: 1.23), "USD1.23")
-        XCTAssertEqual(formatter.string(from: 123.4), "USD123.40")
-
-        // If .minimumIntegerDigits is not set before .numberStyle change, update the value
-        let formatter2 = NumberFormatter()
-        XCTAssertEqual(formatter2.minimumIntegerDigits, 0)
-        formatter2.numberStyle = .currencyISOCode
-        XCTAssertEqual(formatter2.minimumIntegerDigits, 1)
-        formatter2.locale = Locale(identifier: "en_US")
-        XCTAssertEqual(formatter2.string(from: 0.01), "USD0.01")
-        XCTAssertEqual(formatter2.string(from: 1.234), "USD1.23")
-        XCTAssertEqual(formatter2.string(from: 123456.7), "USD123,456.70")
-    }
-
-    func test_currencyAccountingMinimumIntegerDigits() {
-        // If .minimumIntegerDigits is set to 0 before .numberStyle change, preserve the value
-        let formatter = NumberFormatter()
-        XCTAssertEqual(formatter.minimumIntegerDigits, 0)
-        formatter.minimumIntegerDigits = 0
-        formatter.numberStyle = .currencyAccounting
-        XCTAssertEqual(formatter.minimumIntegerDigits, 0)
-        formatter.locale = Locale(identifier: "en_US")
-        XCTAssertEqual(formatter.string(from: 0), "$.00")
-        XCTAssertEqual(formatter.string(from: 1.23), "$1.23")
-        XCTAssertEqual(formatter.string(from: 123.4), "$123.40")
-
-        // If .minimumIntegerDigits is not set before .numberStyle change, update the value
-        let formatter2 = NumberFormatter()
-        XCTAssertEqual(formatter2.minimumIntegerDigits, 0)
-        formatter2.numberStyle = .currencyAccounting
-        XCTAssertEqual(formatter2.minimumIntegerDigits, 1)
-        formatter2.locale = Locale(identifier: "en_US")
-        XCTAssertEqual(formatter2.string(from: 0), "$0.00")
-        XCTAssertEqual(formatter2.string(from: 1.23), "$1.23")
-        XCTAssertEqual(formatter2.string(from: 123.4), "$123.40")
-    }
-
     func test_maximumIntegerDigits() {
         let numberFormatter = NumberFormatter()
         numberFormatter.maximumIntegerDigits = 3