Apply suggestions from code review

Co-authored-by: Fabian Engelniederhammer <92720311+fengelniederhammer@users.noreply.github.com>

README.md

@@ -51,7 +51,7 @@ For testing we added multiple users to the realm. The users are:
 ### Group management
 
  - Groups are entities managed by the backend, uniquely identified by a name.
- - Sequence entries are owned by a group, any modification to a sequence entry must be authorized by a member of the group.
+ - Every sequence entry is owned by the group that it was initially submitted for. Modifications (edits while staging, revisions, revocations) can only be made by members of that group.
  - Each user can be a member of multiple groups.
  - Users can create new groups, becoming the initial member automatically.
  - Group members have the authority to add or remove other members.

backend/docs/runtime_view.md

@@ -50,7 +50,8 @@ The following diagram shows the different statuses and their transitions. The **
 
 To revise a sequence entry that has been released (i.e., the status is APPROVED_FOR_RELEASE),
 the user calls the `/revise` endpoint and sends accessions and unpreprocessed data.
-For each revised sequence entry, the user has to be part of the group for which the entry was initially submitted. Then a new row in the "sequenceEntries" table is created.
+For each revised sequence entry, the user has to be part of the group for which the entry was initially submitted.
+Then a new row in the "sequenceEntries" table is created.
 It does not change any existing rows and does not create new accessions.
 The new rows have an incremented version number.
 

backend/src/main/kotlin/org/loculus/backend/controller/SubmissionControllerDescriptions.kt

@@ -115,12 +115,11 @@ The user submits data on behalf of a group that they must be a member of.
 const val REVISE_DESCRIPTION = """
 Submit revised data for new accession versions as multipart/form-data. The following rules apply:
  - Given sequence entries must exist (identified by the column 'accession' in the metadata file) 
- - The user has the right to revise all of the sequence entries (the user is part of the group for that a sequence 
-entry was initially submitted)
+ - The submitting user is member of the group that a sequence entry was initially submitted for.
  - The last accession version is in status  'APPROVED_FOR_RELEASE', i.e. revisable
  - The provided files contain only specified content
  
-If any of above does not apply, this will return an error and roll back the whole transaction.
+If any of above is not fulfilled, this will return an error and roll back the whole transaction.
 """
 
 const val DELETE_SEQUENCES_DESCRIPTION = """