is English Letter
Checks if this character matches pattern [a-zA-Z].
Samples
import dev.kikugie.commons.text.countMatching
import dev.kikugie.commons.text.countWhile
import dev.kikugie.commons.text.getOrDefault
import dev.kikugie.commons.text.isEnglishLetter
import dev.kikugie.commons.text.isEnglishLetterOrDigit
import dev.kikugie.commons.text.reverseView
import kotlin.test.assertEquals
import kotlin.test.assertFalse
import kotlin.test.assertTrue
fun main() {
//sampleStart
assertTrue('a'.isEnglishLetter())
assertFalse('1'.isEnglishLetter())
assertFalse('ッ'.isEnglishLetter())
//sampleEnd
}