Update README.md

# Update of the ASN.1 file

The following steps shall be followed to update the ASN.1 file in TS 103 666-1:

1. CR is accepted by SCP Plenary which modifies any of the ASN.1 snippets in TS 103 666-1.

1. CR is accepted by SET Plenary which modifies any of the ASN.1 snippets in TS 103 666-1.

2. Implement the CR(s) in a new draft of the specification to be published.

3. Generate complete ASN.1 file from the draft of the specification. This can be performed using the tools_extract_asn1.py script.

4. Make sure that the generated ASN.1 file compiles successfully using any ASN.1 compiler.

5. Submit generated ASN.1 file to Git repository. CR number and SCP document number shall be mentioned in the commit message.

5. Submit generated ASN.1 file to Git repository. CR number and SET document number shall be mentioned in the commit message.

6. Update Annex L.2 in the draft of TS 103 666-1 with Git link to updated ASN.1 file.

7. Start publication process of the new version of TS 103 666-1.