fix(spec/npm): port #116 - add '~>' alias

Add `~>` as an alias for `~`

Credit to `@gnattishness`, author of [`python-semanticversion #116`].

[`python-semanticversion #116`]: rbarrois/python-semanticversion#116

Author: jjmaestro

spec/internal/npm.bzl

@@ -226,7 +226,7 @@ _OP = dict(
 )
 OP = struct(**_OP)
 
-OP_ALIASES = {"": "="}
+OP_ALIASES = {"": "=", "~>": "~"}
 
 npmparser = struct(
     new = _npm_parser_new,

tests/spec/spec_npm.bzl

@@ -98,6 +98,7 @@ def _expand_impl(ctx):
         ("~0.2", ">=0.2.0 <0.3.0"),
         ("~0", ">=0.0.0 <1.0.0"),
         ("~1.2.3-beta.2", ">=1.2.3-beta.2 <1.3.0"),
+        ("~>1.2.3", ">=1.2.3 <1.3.0"),
 
         # Caret ranges
         ("^1.2.3", ">=1.2.3 <2.0.0"),