Add support of php 7.2

Author: ilyakharev

.github/workflows/tests.yml

@@ -25,7 +25,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        php-versions: [ '7.4' ]
+        php-versions: [ '7.2' ]
     steps:
       - uses: actions/checkout@v3
         name: Checkout

CHANGELOG.md

@@ -1,3 +1,5 @@
+* added support of php 7.2
+
 ## 1.5.5
 
 * fixed iam auth for PHP < 8.0

composer.json

@@ -9,7 +9,7 @@
         }
     ],
     "require": {
-        "php": ">=7.3",
+        "php": ">=7.2",
         "ext-bcmath": "*",
         "ext-curl": "*",
         "ext-grpc": "*",