chore(deps): update dependency terser to v1.2.0

Gemfile.lock

@@ -30,7 +30,7 @@ GEM
     ethon (0.16.0)
       ffi (>= 1.15.0)
     eventmachine (1.2.7)
-    execjs (2.8.1)
+    execjs (2.9.1)
     exifr (1.4.0)
     ffi (1.15.5)
     fspath (3.1.2)
@@ -125,7 +125,7 @@ GEM
     strings-ansi (0.2.0)
     terminal-table (3.0.2)
       unicode-display_width (>= 1.1.1, < 3)
-    terser (1.1.20)
+    terser (1.2.0)
       execjs (>= 0.3.0, < 3)
     thin (1.8.2)
       daemons (~> 1.0, >= 1.0.9)