Upgrade version of @sentry/netlify-build-plugin

[jonesphillip]

Upgrade version of @sentry/netlify-build-plugin to 1.0.3

Are you adding a plugin or updating one?

• Adding a plugin
• Updating a plugin

Plugin version diff
https://diff.intrinsic.com/@sentry/netlify-build-plugin/1.0.2/1.0.3

Have you completed the following?

• Read and followed the plugin author guidelines.
• Included all required fields in your entry.
• Tested the plugin locally and on Netlify, using the plugin version stated in your entry.

Test plan
Tested new changes, deploy successful

[ehmicky]

Thanks!