Update golang Docker tag to v1.22 (#34)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| golang | stage | minor | `1.21-alpine3.18` -> `1.22-alpine3.18` |
| golang | final | minor | `1.21-alpine3.18` -> `1.22-alpine3.18` |

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Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.21-alpine3.18 AS builder
+FROM golang:1.22-alpine3.18 AS builder
 
 WORKDIR /app
 

test/Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.21-alpine3.18 AS builder
+FROM golang:1.22-alpine3.18 AS builder
 
 WORKDIR /src