deps: Upgrade ast-types to my branch with ImportSpecifier fix

I've sent the fix as a PR:
  benjamn/ast-types#745
which hopefully will get merged in due course.  In the meantime,
start using it.

Like Recast, the library needs a build step, so add that to our
postinstall script.

Author: gnprice

package.json

@@ -10,7 +10,7 @@
   },
   "homepage": "https://github.com/gnprice/tsflower",
   "dependencies": {
-    "ast-types": "^0.14.2",
+    "ast-types": "gnprice/ast-types#24ac46577",
     "recast": "gnprice/recast#3cf24324c",
     "typescript": "^4.6.3"
   },
@@ -23,9 +23,9 @@
     "tsflower": "bin/tsflower"
   },
   "scripts": {
-    "postinstall": "cd node_modules/recast && npm install && npm run build || :",
+    "postinstall": "( cd node_modules/recast && npm install && npm run build || : ) && ( cd node_modules/ast-types && npm install )",
     "prepublishOnly": "npm run build",
     "test": "t/run",
     "build": "tsc"
   }
-}
+}

yarn.lock

@@ -7,17 +7,9 @@
   resolved "https://registry.yarnpkg.com/@types/node/-/node-17.0.27.tgz#f4df3981ae8268c066e8f49995639f855469081e"
   integrity sha512-4/Ke7bbWOasuT3kceBZFGakP1dYN2XFd8v2l9bqF2LNWrmeU07JLpp56aEeG6+Q3olqO5TvXpW0yaiYnZJ5CXg==
 
-[email protected]:
+[email protected], ast-types@gnprice/ast-types#24ac46577:
   version "0.15.2"
-  resolved "https://registry.yarnpkg.com/ast-types/-/ast-types-0.15.2.tgz#39ae4809393c4b16df751ee563411423e85fb49d"
-  integrity sha512-c27loCv9QkZinsa5ProX751khO9DJl/AcB5c2KNtA6NRvHKS0PgLfcftz72KVq504vB0Gku5s2kUZzDBvQWvHg==
-  dependencies:
-    tslib "^2.0.1"
-
-ast-types@^0.14.2:
-  version "0.14.2"
-  resolved "https://registry.yarnpkg.com/ast-types/-/ast-types-0.14.2.tgz#600b882df8583e3cd4f2df5fa20fa83759d4bdfd"
-  integrity sha512-O0yuUDnZeQDL+ncNGlJ78BiO4jnYI3bvMsD5prT0/nsgijG/LpNBIr63gTjVTNsiGkgQhiyCShTgxt8oXOrklA==
+  resolved "https://codeload.github.com/gnprice/ast-types/tar.gz/24ac46577b1fa7587e3741b827339f18711f2bc6"
   dependencies:
     tslib "^2.0.1"