Shortcode Embeds: Amazon Ads <Script> replaced with <a href> In Extra Theme

When using the Extra-Ads widget from the [Extra theme from Elegant Themes](https://www.elegantthemes.com/gallery/extra/) a conflict is present replacing `` with `<a href=` I was not able to replicate this with the Text widget in Text Mode.

#### Steps to reproduce the issue

1.Install and activate Extra
2. Install and activate Jetpack
3. Insert the `Ads - Extra` widget into the site.
4. Add the Amazon Ad code
```
<div class="alignleft">
<script type="text/javascript">
amzn_assoc_ad_type = "banner";
amzn_assoc_marketplace = "amazon";
amzn_assoc_region = "US";
amzn_assoc_placement = "assoc_banner_placement_default";
amzn_assoc_campaigns = "amazonhomepage_2017";
amzn_assoc_banner_type = "rotating";
amzn_assoc_p = "9";
amzn_assoc_width = "180";
amzn_assoc_height = "150";
amzn_assoc_tracking_id = "ewsrocessi-20";
amzn_assoc_linkid = "####";



```

Upon save watch the second `` tag be replaced with:
``` <a href="//z-na.amazon-adsystem.com/widgets/q?ServiceVersion=20070822&#038;Operation=GetScript&#038;ID=OneJS&#038;WS=1">//z-na.amazon-adsystem.com/widgets/q?ServiceVersion=20070822&#038;Operation=GetScript&#038;ID=OneJS&#038;WS=1</a>```

If you repeat steps 3-4 above with Enhanced Distribution turned off the second script tag remains.

#### What I expected
For the `<script>` tag to remain untouched upon saving the widget.

#### What happened instead
Final `<script>` tag gets replaced with `href="`

#### Screenshot

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Start by reproducing the issue with the Extra-Ads widget, Jetpack, and Enhanced Distribution enabled, using the Amazon ad code from the report. Compare the saved widget output with Enhanced Distribution disabled; done means the second script tag remains a script tag and its attributes are not converted into a link.

Written by the indexing model from the issue text.