Adding pcre2 dependency for >= 1.8 (#23)

Author: beta-ziliani

index.js

@@ -120,9 +120,13 @@ async function installCrystalForLinux({crystal, shards, arch = getArch(), path})
     const filePatterns = {"x86_64": /-linux-x86_64\.tar\.gz$/, "x86": /-linux-i686\.tar\.gz$/};
     checkArch(arch, Object.keys(filePatterns));
 
-    const depsTask = installAptPackages(
-        "libevent-dev libgmp-dev libpcre3-dev libssl-dev libxml2-dev libyaml-dev".split(" "),
-    );
+    let packages = "libevent-dev libgmp-dev libpcre3-dev libssl-dev libxml2-dev libyaml-dev".split(" ");
+    if (crystal === Latest || crystal === Nightly || cmpTags(crystal, "1.8") >= 0) {
+        packages.push("libpcre2-dev");
+    }
+
+    const depsTask = installAptPackages(packages);
+
     await installBinaryRelease({crystal, shards, filePattern: filePatterns[arch], path});
 
     Core.info("Setting up environment for Crystal");