fix: Remove end_invocation check to ensure after_agent callbacks execute #1761

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@rcleveng

The following contributors were found for this pull request:

✅ 2d4ef2e Author: @rcleveng <r**@robsite.org>, <rcleveng@users.noreply.github.com>
✅ 6ed59eb Author: @sindrigunnars <sindr***********rsson@gmail.com>
✅ 95d2557 Author: @hangfei <ha****i@google.com>
✅ 05db353 Author: @DeanChensj <de****en@google.com>
✅ 4357691 Author: @rahulsamant37 <161972011+rahulsamant37@users.noreply.github.com>
✅ 4b40157 Author: @seanzhougoogle <sean*******gle@google.com>
✅ 6cbab62 Author: @jcpagadora737 <jcp*****ra@google.com>
✅ be1d989 Author: @anmourchen <yan*****en@google.com>
✅ f6df4a6 Author: @abchang123 <ar*****ng@google.com>
✅ eaacd9b Author: @wyf7107 <wa***f@google.com>
✅ e993ba4 Author: @genquan9 <ge****n@google.com>
✅ ca77f9f Author: @wuliang229 <wu****g@google.com>
✅ 49bcdfb Author: <xy****le@google.com>

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