Update markdownlint version and fix violation (open-telemetry#1010)

Author: Liudmila Molkova

.markdownlint.yaml

@@ -13,3 +13,6 @@ ol-prefix:
 no-inline-html: false
 fenced-code-language: false
 no-space-in-code: false
+first-line-h1: false
+no-duplicate-heading:
+  siblings_only: true

docs/messaging/kafka.md

@@ -66,7 +66,7 @@ Process CA:              | Span Rcv1 |
 Process CB:                           | Span Rcv2 |
 ```
 
-| Field or Attribute | Span Prod1 | Span Rcv1 | Span Proc1 | Span Prod2 | Span Rcv2
+| Field or Attribute | Span Prod1 | Span Rcv1 | Span Proc1 | Span Prod2 | Span Rcv2 |
 |-|-|-|-|-|-|
 | Span name | `"T1 publish"` | `"T1 receive"` | `"T1 process"` | `"T2 publish"` | `"T2 receive`" |
 | Parent |  | Span Prod1 | Span Rcv1 | Span Rcv1 | Span Prod2 |

package.json

@@ -13,7 +13,7 @@
     "js-yaml": "^4.1.0",
     "markdown-link-check": "3.11.2",
     "markdown-toc": "^1.2.0",
-    "markdownlint": "^0.29.0",
+    "markdownlint": "0.34.0",
     "markdownlint-cli": "0.31.0",
     "prettier": "^3.0.0",
     "through2": "^4.0.2"