build(deps-dev): Bump jsii-docgen from 1.8.86 to 1.8.88 (#354)

Bumps [jsii-docgen](https://github.com/eladb/jsii-docgen) from 1.8.86 to 1.8.88.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/eladb/jsii-docgen/releases">jsii-docgen's releases</a>.</em></p>
<blockquote>
<h2>v1.8.88</h2>
<h3><a href="https://github.com/eladb/jsii-docgen/compare/v1.8.87...v1.8.88">1.8.88</a> (2021-06-06)</h3>
<h2>v1.8.87</h2>
<h3><a href="https://github.com/eladb/jsii-docgen/compare/v1.8.86...v1.8.87">1.8.87</a> (2021-06-06)</h3>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/cdklabs/jsii-docgen/commit/53cb99f71861ceb5ccbd599bffd05ff414d7b52a"><code>53cb99f</code></a> chore(deps): upgrade dependencies (<a href="https://github-redirect.dependabot.com/eladb/jsii-docgen/issues/329">#329</a>)</li>
<li><a href="https://github.com/cdklabs/jsii-docgen/commit/539d4078f54c414b40e254e8f696eca4e092441e"><code>539d407</code></a> chore(deps): upgrade projen (<a href="https://github-redirect.dependabot.com/eladb/jsii-docgen/issues/332">#332</a>)</li>
<li>See full diff in <a href="https://github.com/eladb/jsii-docgen/compare/v1.8.86...v1.8.88">compare view</a></li>
</ul>
</details>
<br />


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</details>

yarn.lock

@@ -485,7 +485,7 @@
     "@types/yargs" "^15.0.0"
     chalk "^4.0.0"
 
-"@jsii/spec@^1.16.0", "@jsii/spec@^1.30.0":
+"@jsii/spec@^1.30.0":
   version "1.30.0"
   resolved "https://registry.yarnpkg.com/@jsii/spec/-/spec-1.30.0.tgz#e5b2381b2be0b9c0839190f9f45d0a038654c73d"
   integrity sha512-oXIwvZyHHc/TrwA/3pzQ3gkqBe916EWBvaexNI3rnKZujlHZT4vVVHMCjQ/kUJhcR0GEaahvwlNhiPTu6roC2g==
@@ -3634,13 +3634,13 @@ jsii-diff@^1.19.0:
     yargs "^16.2.0"
 
 jsii-docgen@^1.8.33:
-  version "1.8.86"
-  resolved "https://registry.yarnpkg.com/jsii-docgen/-/jsii-docgen-1.8.86.tgz#e5d0373971a6e24fdea23ac2c85d1dcb29b4de6a"
-  integrity sha512-wMJjMSz/Lqjm+invtVPg0XlCpMtDscKLK9fO2MugzU42I6LuRAIdszZlZ+Nii3ws/2JSHon1J8vVR49lFTUuig==
+  version "1.8.88"
+  resolved "https://registry.yarnpkg.com/jsii-docgen/-/jsii-docgen-1.8.88.tgz#b0eba7d98f20bb0aeecb4bb8dc13b00f985b3b85"
+  integrity sha512-CTW585S3G0mjRuVQBZDke2eE+E5DwDavH10LxOJbZWYT7XpDyKw+LytqwEofjPfy426Yrq3wzvKrjEL7lcoagg==
   dependencies:
-    "@jsii/spec" "^1.16.0"
-    fs-extra "^9.0.1"
-    jsii-reflect "^1.16.0"
+    "@jsii/spec" "^1.30.0"
+    fs-extra "^9.1.0"
+    jsii-reflect "^1.30.0"
     yargs "^16.2.0"
 
 jsii-pacmak@^1.19.0, jsii-pacmak@^1.29.0:
@@ -3661,7 +3661,7 @@ jsii-pacmak@^1.19.0, jsii-pacmak@^1.29.0:
     xmlbuilder "^15.1.1"
     yargs "^16.2.0"
 
-jsii-reflect@^1.16.0, jsii-reflect@^1.30.0:
+jsii-reflect@^1.30.0:
   version "1.30.0"
   resolved "https://registry.yarnpkg.com/jsii-reflect/-/jsii-reflect-1.30.0.tgz#b079d448ed35c9d9dfea8798a8ef39487ed0c86c"
   integrity sha512-t/1Zr1gGqQSYt94Lfq860VLnCr8y8MLvlLorWYqmBeWKCaSPhtYSC1blGhZhDrAW+CBXiT0Oy64j4Q++AntRmw==