chore(main): release 2.61.0 (#3867)

🤖 I have created a release *beep* *boop*
---


<details><summary>2.61.0</summary>

##
[2.61.0](v2.60.2...v2.61.0)
(2025-08-04)


### Features

* **mtls:** Add support for X.509-based mTLS-transport in Java GAX lib
([#3852](#3852))
([2d02344](2d02344))


### Bug Fixes

* improve error messaging for LRO CancellationException
([#3873](#3873))
([9cae675](9cae675))
* make generation config update logs verbose
([#3764](#3764))
([9b1a34b](9b1a34b))
</details>

---
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Please](https://github.com/googleapis/release-please). See
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Co-authored-by: release-please[bot] <55107282+release-please[bot]@users.noreply.github.com>

Author: release-please[bot]

gapic-generator-java-bom/pom.xml

@@ -127,12 +127,12 @@
       <dependency>
         <groupId>com.google.api.grpc</groupId>
         <artifactId>proto-google-iam-v3</artifactId>
-        <version>1.54.3-SNAPSHOT</version><!-- {x-version-update:proto-google-iam-v3:current} -->
+        <version>1.55.0</version><!-- {x-version-update:proto-google-iam-v3:current} -->
       </dependency>
       <dependency>
         <groupId>com.google.api.grpc</groupId>
         <artifactId>proto-google-iam-v3beta</artifactId>
-        <version>1.54.3-SNAPSHOT</version><!-- {x-version-update:proto-google-iam-v3beta:current} -->
+        <version>1.55.0</version><!-- {x-version-update:proto-google-iam-v3beta:current} -->
       </dependency>
 
       <!-- Following test deps are kept to keep them consistent with versions above -->
@@ -164,12 +164,12 @@
       <dependency>
         <groupId>com.google.api.grpc</groupId>
         <artifactId>grpc-google-iam-v3</artifactId>
-        <version>1.54.3-SNAPSHOT</version><!-- {x-version-update:grpc-google-iam-v3:current} -->
+        <version>1.55.0</version><!-- {x-version-update:grpc-google-iam-v3:current} -->
       </dependency>
       <dependency>
         <groupId>com.google.api.grpc</groupId>
         <artifactId>grpc-google-iam-v3beta</artifactId>
-        <version>1.54.3-SNAPSHOT</version><!-- {x-version-update:grpc-google-iam-v3beta:current} -->
+        <version>1.55.0</version><!-- {x-version-update:grpc-google-iam-v3beta:current} -->
       </dependency>
     </dependencies>
 

java-iam/pom.xml

@@ -145,12 +145,12 @@
       <dependency>
         <groupId>com.google.api.grpc</groupId>
         <artifactId>proto-google-iam-v3</artifactId>
-        <version>1.54.3-SNAPSHOT</version><!-- {x-version-update:proto-google-iam-v3:current} -->
+        <version>1.55.0</version><!-- {x-version-update:proto-google-iam-v3:current} -->
       </dependency>
       <dependency>
         <groupId>com.google.api.grpc</groupId>
         <artifactId>grpc-google-iam-v3</artifactId>
-        <version>1.54.3-SNAPSHOT</version><!-- {x-version-update:grpc-google-iam-v3:current} -->
+        <version>1.55.0</version><!-- {x-version-update:grpc-google-iam-v3:current} -->
       </dependency>
       <dependency>
         <groupId>javax.annotation</groupId>