Expose EN_US fixture crate-wide

The checker, lib and suggester all use it for testing. We can use only
one instance by making these constants/statics on the crate instead of
per-module.

src/checker.rs

@@ -2287,16 +2287,8 @@ impl<'aff> CompoundingResult<'aff> {
 
 #[cfg(test)]
 mod test {
-    use once_cell::sync::Lazy;
-
     use super::*;
-
-    const EN_US_AFF: &str = include_str!("../vendor/en_US/en_US.aff");
-    const EN_US_DIC: &str = include_str!("../vendor/en_US/en_US.dic");
-
-    // It's a little overkill to use a real dictionary for unit tests but it compiles so
-    // quickly that if we only compile it once it doesn't really slow down the test suite.
-    static EN_US: Lazy<Dictionary> = Lazy::new(|| Dictionary::new(EN_US_AFF, EN_US_DIC).unwrap());
+    use crate::EN_US;
 
     #[test]
     fn are_three_chars_equal_test() {

src/lib.rs

@@ -513,14 +513,20 @@ fn erase_chars<'a>(word: &'a str, ignore: &[char]) -> Cow<'a, str> {
     }
 }
 
+#[cfg(test)]
+const EN_US_AFF: &str = include_str!("../vendor/en_US/en_US.aff");
+#[cfg(test)]
+const EN_US_DIC: &str = include_str!("../vendor/en_US/en_US.dic");
+// It's a little overkill to use a real dictionary for unit tests but it compiles so
+// quickly that if we only compile it once it doesn't slow down the test suite.
+#[cfg(test)]
+static EN_US: once_cell::sync::Lazy<Dictionary> =
+    once_cell::sync::Lazy::new(|| Dictionary::new(EN_US_AFF, EN_US_DIC).unwrap());
+
 #[cfg(test)]
 mod test {
     use super::*;
 
-    const EN_US_AFF: &str = include_str!("../vendor/en_US/en_US.aff");
-    const EN_US_DIC: &str = include_str!("../vendor/en_US/en_US.dic");
-    // static EN_US: Lazy<Dictionary> = Lazy::new(|| Dictionary::new(EN_US_AFF, EN_US_DIC).unwrap());
-
     macro_rules! flag {
         ( $x:expr ) => {{
             Flag::new($x as u16).unwrap()