deps: update dependency com.google.truth.extensions:truth-proto-extension to v1.2.0 (#2035)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.truth.extensions:truth-proto-extension](https://togithub.com/google/truth) | `1.1.5` -> `1.2.0` | [![age](https://developer.mend.io/api/mc/badges/age/maven/com.google.truth.extensions:truth-proto-extension/1.2.0?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/com.google.truth.extensions:truth-proto-extension/1.2.0?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/com.google.truth.extensions:truth-proto-extension/1.1.5/1.2.0?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/com.google.truth.extensions:truth-proto-extension/1.1.5/1.2.0?slim=true)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>google/truth (com.google.truth.extensions:truth-proto-extension)</summary>

### [`v1.2.0`](https://togithub.com/google/truth/releases/tag/v1.2.0): 1.2.0

[Compare Source](https://togithub.com/google/truth/compare/v1.1.5...v1.2.0)

-   Fixed a bug that caused ProtoTruth to ignore the contents of unpacked `Any` messages. This fix may cause tests to fail, since ProtoTruth will now check whether the message contents match. If so, you may need to change the values that your tests expect, or there may be a bug in the code under test that had been hidden by the Truth bug. Sorry for the trouble. ([`8bd3ef6`](https://togithub.com/google/truth/commit/8bd3ef613))
-   Added `isWithin().of()` support to `IntegerSubject` and `LongSubject`. ([`6464cb5`](https://togithub.com/google/truth/commit/6464cb5ca), [`0e99a27`](https://togithub.com/google/truth/commit/0e99a2711))

</details>

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Author: renovate-bot

pom.xml

@@ -189,7 +189,7 @@
             <dependency>
                 <groupId>com.google.truth.extensions</groupId>
                 <artifactId>truth-proto-extension</artifactId>
-                <version>1.1.5</version>
+                <version>1.2.0</version>
                 <scope>test</scope>
                 <exclusions>
                     <!-- exclude protobuf-java as it is managed in the shared deps bom-->