minor #21102 Fix lint major symfony version from 7 to 8 (vinceAmstoutz)

This PR was merged into the 8.0 branch.

Discussion
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Fix lint major symfony version from 7 to 8

Solves failed pipelines for `8.0` branch.

Example: PR #21101 (job https://github.com/symfony/symfony-docs/actions/runs/15779150078/job/44480309482)

Commits
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25d3085 docs(core): update symfony major version from 7 to 8

Author: javiereguiluz

.doctor-rst.yaml

@@ -81,10 +81,10 @@ rules:
         min_version: '8.0'
 
     deprecated_directive_major_version:
-        major_version: 7
+        major_version: 8
 
     deprecated_directive_min_version:
-        min_version: '7.0'
+        min_version: '8.0'
 
 exclude_rule_for_file:
     - path: configuration/multiple_kernels.rst