[Doc] fix resource-scopes broken link missing .md

[masters3d]

Looks like github requires .md to be specified when adding #tags

Contributing a Pull Request

If you haven't already, read the full contribution guide. The guide may have changed since the last time you read it, so please double-check. Once you are done and ready to submit your PR, run through the relevant checklist below.

Contributing to documentation

• The contribution does not exist in any of the docs in either the root of the docs directory or the specs

Contributing an example

• I have checked that there is not an equivalent example already submitted
• I have resolved all warnings and errors shown by the Bicep VS Code extension
• I have checked that all tests are passing by running dotnet test
• I have consistent casing for all of my identifiers and am using camelCasing unless I have a justification to use another casing style

Contributing a feature

• I have opened a new issue for the proposal, or commented on an existing one, and ensured that the Bicep maintainers are good with the design of the feature being implemented
• I have included "Fixes #{issue_number}" in the PR description, so GitHub can link to the issue and close it when the PR is merged
• I have appropriate test coverage of my new feature

Contributing a snippet

• I have only a single resource in my snippet

• I have checked that there is not an equivalent snippet already submitted

• I have used camelCasing unless I have a justification to use another casing style

• I have placeholders values that correspond to their property names (e.g. dnsPrefix: 'dnsPrefix'), unless it's a property that MUST be changed or parameterized in order to deploy. In that case, I use 'REQUIRED' e.g. keyData

• I have my symbolic name as the first tab stop ($1) in the snippet. e.g. res-aks-cluster.bicep

• I have a resource name property equal to "name"

  e.g.

  resource aksCluster 'Microsoft.ContainerService/managedClusters@2021-03-01' = {
    name: 'name'

[majastrz]

Thanks for fixing!