[PM-6274] [deps]: Update rust Docker tag to v1.76 (#611)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| rust | stage | minor | `1.73` -> `1.76` |

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[PM-6274](https://bitwarden.atlassian.net/browse/PM-6274)

[PM-6274]:
https://bitwarden.atlassian.net/browse/PM-6274?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

crates/bws/Dockerfile

@@ -1,7 +1,7 @@
 ###############################################
 #                 Build stage                 #
 ###############################################
-FROM --platform=$BUILDPLATFORM rust:1.73 AS build
+FROM --platform=$BUILDPLATFORM rust:1.76 AS build
 
 # Docker buildx supplies the value for this arg
 ARG TARGETPLATFORM